TY - JOUR. T1 - VNTR allele frequency distributions under the stepwise mutation model. T2 - A computer simulation approach. AU - Shriver, M. D.. AU - Jin, L.. AU - Chakraborty, R.. AU - Boerwinkle, E.. N1 - Copyright: Copyright 2004 Elsevier B.V., All rights reserved.. PY - 1993. Y1 - 1993. N2 - Variable numbers of tandem repeats (VNTRs) are a class of highly informative and widely dispersed genetic markers. Despite their wide application in biological science, little is known about their mutational mechanisms or population dynamics. The objective of this work was to investigate four summary measures of VNTR allele frequency distributions: number of alleles, number of modes, range in allele size and heterozygosity, using computer simulations of the one-step stepwise mutation model (SMM). We estimated these measures and their probability distributions for a wide range of mutation rates and compared the simulation results with predictions from analytical formulations of the one-step SMM. The ...

We previously reported that the human immunodeficiency virus type 1 NL4-3 Nef is necessary and sufficient to induce a severe AIDS-like disease in transgenic (Tg) mice when the protein is expressed under the regulatory sequences of the human CD4 gene. We have now assayed additional Nef alleles (SF2, JR-CSF, YU10x, and NL4-3 [T71R] Nef alleles), including some from long-term nonprogressors (AD-93, 032an, and 039nm alleles) in the same Tg system and compared their pathogenicities. All these Nef alleles downregulated cell surface CD4 in human cells in vitro and also, with the exception of NefYU10x, in Tg CD4+ T cells. Depletion of double-positive and single-positive thymocytes occurred with all alleles but was less pronounced in NefYU10x Tg mice. A loss of peripheral CD4+ T cells was observed with all alleles but was minimal in NefYU10x Tg mice. In Nef032an and NefSF2 Tg mice, T-cell loss was severe despite lower levels of Tg expression, suggesting a higher virulence of these alleles. All Nef ...

TY - JOUR. T1 - APOE alleles association with cognitive function differs across Hispanic/Latino groups and genetic ancestry in the study of Latinos-investigation of neurocognitive aging (HCHS/SOL). AU - Granot-Hershkovitz, Einat. AU - Tarraf, Wassim. AU - Kurniansyah, Nuzulul. AU - Daviglus, Martha. AU - Isasi, Carmen R.. AU - Kaplan, Robert. AU - Lamar, Melissa. AU - Perreira, Krista M.. AU - Wassertheil-Smoller, Sylvia. AU - Stickel, Ariana. AU - Thyagarajan, Bharat. AU - Zeng, Donglin. AU - Fornage, Myriam. AU - DeCarli, Charles S.. AU - González, Hector M.. AU - Sofer, Tamar. N1 - Funding Information: The authors thank the staff and participants of HCHS/SOL for their important contributions. Investigators website: http://www.cscc.unc.edu/hchs/ . This work is supported by the National Institute on Aging (R01AG048642, RF1AG054548, RF1AG061022, and R21AG056952). Dr. González also receives additional support from P30AG062429 and P30AG059299. The Hispanic Community Health Study/Study of ...

Sequencing the transcriptome can answer various questions such as determining the transcripts expressed in a given species for a specific tissue or condition, evaluating differential expression, discovering variants, and evaluating allele-specific expression. Differential expression evaluates the expression differences between different strains, tissues, and conditions. Allele-specific expression evaluates expression differences between parental alleles. Both differential expression and allele-specific expression have been studied for heterosis (hybrid vigor), where the hybrid has improved performance over the parents for one or more traits. The Allele Workbench software was developed for a heterosis study that evaluated allele-specific expression for a mouse F1 hybrid using libraries from multiple tissues with biological replicates. This software has been made into a distributable package, which includes a pipeline, a Java interface to build the database, and a Java interface for query and display of

Previous studies have identified a central role for HLA-B alleles in influencing control of HIV infection. An alternative possibility is that a small number of HLA-B alleles may have a very strong impact on HIV disease outcome, dominating the contribution of other HLA alleles. Here, we find that even following the exclusion of subjects expressing any of the HLA-B class I alleles (B*57, B*58, and B*18) identified to have the strongest influence on control, the dominant impact of HLA-B alleles on virus set point and absolute CD4 count variation remains significant. However, we also find that the influence of HLA on HIV control in this C-clade-infected cohort from South Africa extends beyond HLA-B as HLA-Cw type remains a significant predictor of virus and CD4 count following exclusion of the strongest HLA-B associations. Furthermore, there is evidence of interdependent protective effects of the HLA-Cw*0401-B*8101, HLA-Cw*1203-B*3910, and HLA-A*7401-B*5703 haplotypes that cannot be explained solely by

Reduced height (Rht) and photoperiod insensitivity (Ppd) allele associations with establishment and early growth of wheat in contrasting production systems ...

In an initial investigation of differential expression of genes caused by cis-acting regulatory elements in rice, the lack of reproducibility led us to question the basic premise of allelic expression imbalance determination: namely that departures of cDNA expression ratios from those observed in genomic DNA provide unequivocal evidence of cis-acting polymorphisms. This paper describes experiments designed to demonstrate that stochastic variation in low copy number of targets in PCR reactions give variable allelic ratios even when starting with the same copy numbers of the two alleles. These significant departures from an expected 1:1 ratio provide an explanation to the lack of reproducibility observed for our cDNA measurements ...

Several studies have found strikingly different allele frequencies between continents. This has been mainly interpreted as being due to local adaptation. However, demographic factors can generate similar patterns. Namely, allelic surfing during a population range expansion may increase the frequency of alleles in newly colonised areas. In this study, we examined 772 STRs, 210 diallelic indels, and 2834 SNPs typed in 53 human populations worldwide under the HGDP-CEPH Diversity Panel to determine to which extent allele frequency differs among four regions (Africa, Eurasia, East Asia, and America). We find that large allele frequency differences between continents are surprisingly common, and that Africa and America show the largest number of loci with extreme frequency differences. Moreover, more STR alleles have increased rather than decreased in frequency outside Africa, as expected under allelic surfing. Finally, there is no relationship between the extent of allele frequency differences and ...

Several studies have found strikingly different allele frequencies between continents. This has been mainly interpreted as being due to local adaptation. However, demographic factors can generate similar patterns. Namely, allelic surfing during a population range expansion may increase the frequency of alleles in newly colonised areas. In this study, we examined 772 STRs, 210 diallelic indels, and 2834 SNPs typed in 53 human populations worldwide under the HGDP-CEPH Diversity Panel to determine to which extent allele frequency differs among four regions (Africa, Eurasia, East Asia, and America). We find that large allele frequency differences between continents are surprisingly common, and that Africa and America show the largest number of loci with extreme frequency differences. Moreover, more STR alleles have increased rather than decreased in frequency outside Africa, as expected under allelic surfing. Finally, there is no relationship between the extent of allele frequency differences and ...

Rasmussen M, Sundström M, Göransson Kultima H, Botling J, Micke P, Birgisson H, Glimelius B, Isaksson A Genome Biol. 12 (10) R108 [2011-10-24; online 2011-10-24] We describe a bioinformatic tool, Tumor Aberration Prediction Suite (TAPS), for the identification of allele-specific copy numbers in tumor samples using data from Affymetrix SNP arrays. It includes detailed visualization of genomic segment characteristics and iterative pattern recognition for copy number identification, and does not require patient-matched normal samples. TAPS can be used to identify chromosomal aberrations with high sensitivity even when the proportion of tumor cells is as low as 30%. Analysis of cancer samples indicates that TAPS is well suited to investigate samples with aneuploidy and tumor heterogeneity, which is commonly found in many types of solid tumors. Affiliated researcher QC bibliography QC xrefs PubMed 22023820. DOI 10.1186/gb-2011-12-10-r108. Crossref 10.1186/gb-2011-12-10-r108. ...

TY - JOUR. T1 - Genotyping and haplotyping of CYP2C19 functional alleles on thin-film biosensor chips. AU - Nakamoto, Kaori. AU - Kidd, Judith R.. AU - Jenison, Robert D.. AU - Klaassen, Curtis D.. AU - Wan, Yu-Jui Yvonne. AU - Kidd, Kenneth K.. AU - Zhong, Xiao Bo. PY - 2007/2. Y1 - 2007/2. N2 - OBJECTIVES: Numerous functional polymorphisms in the CYP2C19 gene have been identified; some alleles (e.g. CYP2C19*2 and CYP2C19*3) are associated with poor metabolism of CYP2C19 substrate drugs. Studies have found that the proportion of poor metabolizers, explained by CYP2C19*2 and CYP2C19*3, varies from less than 50% to more than 90% of poor metabolizers. Therefore, phenotype-genotype correlation studies should cover more than CYP2C19*2 and CYP2C19*3. A broader coverage, however, requires an easy-to-use and high-throughput genotyping platform. This broader coverage should also include the recently identified functional allele, CYP2C19*10, which involves a nucleotide change adjacent to the altered ...

A two-site infinite allele model is constructed to study the effect of intragenic recombination on the number of neutral alleles and the distribution of their frequencies in a finite population. The results of theory and Monte Carlo simulation of the two-site model demonstrate that intragenic recombination significantly increases the mean and variance of the number of alleles when the rates of mutation and recombination are as large as the reciprocal of the population size. Data from natural populations indicate that this may be a significant process in generating variation and determining its distribution.. ...

Objectives: Some patients with rheumatoid arthritis (RA) lack RA-associated human leukocyte antigen (HLA) alleles. Prior studies investigated non-inherited maternal HLA alleles (NIMA) in RA risk with conflicting results.. Methods: We examined NIMA in a large cohort of families from the North American Rheumatoid Arthritis Consortium (NARAC).. Results: Among 620 patients with 1 or both parents having a HLA genotype, patients with RA informative for analysis included 176 without HLA-DRB1*04 and 86 without the HLA shared epitope (SE). The frequency of NIMA encoding HLA-DR4 or the SE was compared to the non-inherited paternal allele (NIPA). DR4-encoding NIMA vs NIPA revealed no significant difference (27% vs 20%). However, parity is known to modulate RA risk and analyses stratified by sex and age of onset showed significant variation among women. Interestingly, among women with onset ,45 years DR4-encoding NIMA was increased compared to NIPA; among women ⩾45 years at onset the reverse was observed ...

PURPOSE: We evaluated allele frequencies and distribution of surfactant protein A2(SP-A2) in Korean neonates in order to estimate the prevalence of RDS, to find out new SP-A alleles, and to establish new steroid therapy. METHODS: Genomic DNA was extracted from 71 neonates and served as a template in PCR for genotype analysis. SP-A gene-specific amplications and gene-specific allele determinations were performed using PCR-cRFLP methods. RESULTS: The distribution for the alleles of the SP-A2 gene in the study population was 1A, 1A0, 1A1, 1A2, 1A3, 1A5, 1A6, 1A7, 1A8, 1A9, 1A11, 1A12. The specific frequencies for the alleles of the SP- A2 gene in the study population were : 1A=11.3%, 1A0=38%, 1A1=12.7%, 1A2=9.2%, 1A5=15.5%, 1A7= 2.9%, 1A8=4.9%, 1A9=2.2%, others=3.3%. CONCLUSION: The frequency of 1A0 was higher than the other SP-A2 alleles in Korean neonates. This finding suggests that the prevalence of RDS in Korea may be low compared with other countries. However, this finding also suggests that ...

The results from this study show that the decreased CYP2D6 activity seen in individuals with the CYP2D6*17 allele is caused by an enzyme with a reduced affinity for some of the CYP2D6 substrates. It was found unexpectedly that a combination of the T107I and R296C substitutions was needed to alter the kinetic properties of the CYP2D6 17 variant, because no significant effect was seen on bufuralol 1′-hydroxylation when they were introduced one by one. In contrast, examination of the rate of O-demethylation of codeine revealed a significant change in the apparentKm when only the T107I substitution was introduced. Also, in the COS-1 expression system, there was a combined effect of the substitutions, affecting the enzyme activity.. The CYP2D6*17 allele is frequently distributed among Zimbabweans [allele frequency of 34.0% (15)], Ethiopians [allele frequency of 9.0% (28)], and other African populations. Thus, more than 10% of the Zimbabwean population is homozygous for this allele, with important ...

Risk of HHV-6 encephalopathy linked to a specific class I HLA-B allele. A group from Japan has conducted a retrospective study of 130 patients who underwent stem cell transplantation in an attempt to identify a risk factor for the development of encephalopathy. Although HLA mismatch and unrelated donor status were strongly associated with HHV-6 reactivation (odds ratio of 5.6 and 4.5, respectively) these factors were not associated with HHV-6 encephalopathy, a condition that can often result in permanent neurologic disability and/or death of the patient.. Interestingly, however, the investigators found a remarkably increased level of risk (odds ratio of 31.1) for the development of encephalopathy when transplant occurred with HLA class I allele HLA-B*40:06 in particular. HLA class I alleles have been associated with several autoimmune diseases as well as viral infections, and higher levels of this allele have been reported in patients with HIV compared to healthy controls. The authors speculate ...

In 62 rare ABO alleles, we identified 29 novel ABO subgroup alleles in 43 apparently unrelated subgroup individuals and their four available pedigrees. Of these alleles, one was a deletion-mutation allele, four were hybrid alleles, and 24 were point-mutation alleles. Most of the point mutations were detected in Exons 6 to 7, while several others were also detected in Exons 1 to 5 or splicing regions. One ABO promoter mutation, −35 to −18 del, was found and verified to reduce promoter activity, as determined by dual luciferase assays. Two mutations, 7G,T and 52C,T, carrying the premature terminal codons E3X and R18X in the 5′-region, were found to be associated with the very weak ABO subgroups Ael and Bel. ...

Common single-nucleotide polymorphisms (SNPs) in ten chromosomal loci have been shown to predispose to colorectal cancer (CRC) in genome-wide association studies. A plausible biological mechanism of CRC susceptibility associated with genetic variation has so far only been proposed for three loci, each pointing to variants that affect gene expression through distant regulatory elements. In this study, we aimed to gain insight into the molecular basis of seven low-penetrance CRC loci tagged by rs4779584 at 15q13, rs10795668 at 10p14, rs3802842 at 11q23, rs4444235 at 14q22, rs9929218 at 16q22, rs10411210 at 19q13, and rs961253 at 20p12. Possible somatic gain of the risk allele or loss of the protective allele was studied by analyzing allelic imbalance in tumour and corresponding normal tissue samples of heterozygous patients. Functional variants were searched from in silico predicted enhancer elements locating inside the CRC-associating linkage-disequilibrium regions. No allelic imbalance targeting the

IDDM2-encoded predisposition to type 1 diabetes has recently been mapped to the minisatellite or variable number of tandem repeat (VNTR) locus upstream of the insulin and insulin-like growth factor II genes on human chromosome 11p15.5. In a UK case-control study (n=228 sporadic diabetics; n=441 healthy controls), we show here that the genotype homozygous for VNTR class I alleles is predisposing to disease (RR=2.68), and VNTR class III alleles are dominantly protective (RR=0.37). In 722 diabetic families from the UK (n=356), USA (n=173), Denmark (n=55) and Sardinia (n=138), we have analysed the transmission of class I alleles to diabetic offspring from class I/III heterozygous parents. We confirm that in families from the USA, class I alleles are transmitted preferentially from fathers. However, in family data sets from the UK, Denmark and Sardinia, the reverse is true and maternal transmission is stronger. Furthermore, in the UK family data set, the difference between maternal and paternal ...

Two genetic mechanisms have been described as potential explanations for heterosis. The first mechanism is dominance. Dominance occurs when there are two differing forms of a gene (alleles) at a given position (locus) on a pair of chromosomes and where one of the pair of alleles masks or over powers the effect of the second. Having two different alleles at a locus is referred to as heterozygosity and the affected individual is heterozygous. Whether an individual has one or two copies of a dominant allele makes little difference in its superiority over others having two copies of the recessive allele. A higher degree of heterozygosity is expected when one population carrying the dominant allele in high frequency is crossed with a second population carrying the recessive allele in high frequency. Alternatively, heterosis may result from joint effects of genes at several loci. This alternative mechanism is called epistasis. Previous research documents reduced performance resulting from the mating of

The human leukocyte antigen (HLA) is a gene complex encoding the major histocompatibility complex (MHC) proteins in humans. The complex is located within the 6p21.3 region on the short arm of human chromosome 6. These genes are highly polymorphic, which means there are many different HLA alleles. More information of HLA and HLA alleles can be found on hla.alleles.org and The IMGT/HLA Database. This is an attempt to plot the rapidly increasing number of HLA alleles over time, with data directly parsed from the IMGT/HLA Statistics page. This notebook file, described below, can be downloaded here.. ...

The advantages of free threshing in wheat led to the selection of the domesticated Q allele which is now present in almost all modern wheat varieties. Q and the pre-domestication allele, q, encode an AP2 transcription factor with the domesticated allele conferring a free threshing character and a subcompact (i.e. partially compact) inflorescence (spike). We demonstrate that mutations in the miR172-binding site of the Q gene are sufficient to increase transcript levels via a reduction in miRNA dependent degradation, consistent with the conclusion that a SNP in the miRNA-binding site of Q relative to q was essential in defining the modern Q allele. We also describe novel gain- and loss-of-function alleles of Q and use these to define new roles for this gene in spike development. Q is required for the suppression of sham ramification and increased Q expression can lead to the formation of ectopic florets and spikelets (specialized inflorescence branches that bear florets and grains) resulting in ...

Hereditary hemochromatosis (HH) is an autosomal recessive trait regarding iron metabolism frequently found in Caucasian populations. The C282Y mutation of the HFE gene, held responsible for HH, has been identified as the major genetic basis for the phenotypic expression of HH whereas two additional mutations of the HFE H63D and S65C gene appear to be associated with a milder form of HH. A high allele frequency of C282Y and H63D has been reported in Northern European populations. In Italy, the overall allele frequency was 0.5% for the C282Y mutation, 12.6% for the H63D mutation and 1.1% for the S65C mutation. In this study, we evaluated the allele frequency of the three principal HFE mutations (C282Y, H63D, S65C) together with eight additional mutations (V53M, H63H, Q127H, E168Q, E168stop, W169stop, V59M, Q238P) in 500 healthy Apulian subjects. No subject homozygous for the C282Y mutation was found while 3% of subjects were heterozygous for this mutation. Heterozygosity and homozygosity for the H63D

We demonstrate how a genetic polymorphism of distinctly different alleles can develop during long-term frequency-dependent evolution in an initially monomorphic diploid population, if mutations have only small phenotypic effect. As a specific example, we use a version of Levenes (1953) soft selection model, where stabilizing selection acts on a continuous trait within each of two habitats. If the optimal phenotypes within the habitats are sufficiently different, then two distinctly different alleles evolve gradually from a single ancestral allele. In a wide range of parameter values, the two locally optimal phenotypes will be realized by one of the homozygotes and the heterozygote, rather than by the two homozygotes. Unlike in the haploid analogue of the model, there can be multiple polymorphic evolutionary attractors with different probabilities of convergence. Our results differ from the population genetic models of short-term evolution in two aspects: (1) a polymorphism that is population ...

For a diploid organism such as human, the two alleles of a particular gene can be expressed at different levels due to X chromosome inactivation, gene imprinting, different local promoter activity, or mRNA stability. Recently, imbalanced allelic expression was found to be common in human and can follow Mendelian inheritance. Here we present a method that employs real competitive PCR for allele-specific expression analysis. A transcribed mutation such as a single nucleotide polymorphism (SNP) is used as the marker for allele-specific expression analysis. A synthetic mutation created in the competitor is close to a natural mutation site in the cDNA sequence. PCR is used to amplify the two cDNA sequences from the two alleles and the competitor. A base extension reaction with a mixture of ddNTPs/dNTP is used to generate three oligonucleotides for the two cDNAs and the competitor. The three products are identified and their ratios are calculated based on their peak areas in the MALDI-TOF mass spectrum.

Abstract: The HLA region harbors some of the most polymorphic loci in the human genome. Among them is the class II locus HLA-DRB1, with more than 400 known alleles. The age of the polymorphism and the rate at which new alleles are generated at HLA loci has caused much controversy over the years. Previous studies have mostly been restricted to the 270 base pairs that constitute the second exon and represent the most variable part of the gene. Here, we investigate the evolutionary history of the HLA-DRB1 locus on the basis of an analysis of 15 genomic full-length alleles (10-15 kb). In addition, the variation in 49 complete coding sequences and 322 exon 2 sequences were analyzed. When excluding exon 2 from the analysis, the diversity at the synonymous sites was found to be similar to the intron diversity. The overall diversity in noncoding region was also similar to the genome average. The DRB1*03 lineage has been found in human, chimpanzee, bonobo, gorilla, and orangutan. An ancestral proto ...

TY - JOUR. T1 - Mutator alleles of yeast DNA polymerase ζ. AU - Sakamoto, Ayako N.. AU - Stone, Jana E.. AU - Kissling, Grace E.. AU - McCulloch, Scott D.. AU - Pavlov, Youri I. AU - Kunkel, Thomas A.. PY - 2007/12/1. Y1 - 2007/12/1. N2 - The yeast REV3 gene encodes the catalytic subunit of DNA polymerase zeta (pol ζ), a B family polymerase that performs mutagenic DNA synthesis in cells. To probe pol ζ mutagenic functions, we generated six mutator alleles of REV3 with amino acid replacements for Leu979, a highly conserved residue inferred to be at the pol ζ active site. Replacing Leu979 with Gly, Val, Asn, Lys, Met or Phe resulted in yeast strains with elevated UV-induced mutant frequencies. While four of these strains had reduced survival following UV irradiation, the rev3-L979F and rev3-L979M strains had normal survival, suggesting retention of pol ζ catalytic activity. UV mutagenesis in the rev3-L979F background was increased when photoproduct bypass by pol η was eliminated by deletion ...

A population size of 100 was simulated for 10 biallelic or multiallelic marker loci for 100 generations before pedigree recording. In each generation, the number of male and female parents was 50 and their alleles were transmitted to descendants on the basis of Mendelian segregation using the gene-dropping method (MacCluer et al. 1986). Parents were randomly mated with a total of two offspring for each of 50 mating pairs. In the multiallelic marker model (e.g., microsatellites), the number of alleles assumed in each marker locus was 4 and base allele frequencies were all at 0.25. In the biallelic marker model (e.g., SNP), the number of alleles was 2 and starting allele frequencies were 0.5. The marker alleles were mutated at rates of 4 × 10−4 per generation in multiallelic markers (Dallas 1992; Weber and Wong 1993; Ellegren 1995) and 2.5 × 10−8 per generation in biallelic markers (Nachman and Crowell 2000). A mutated locus was switched between the two existing alleles for biallelic markers ...

African Americans are disproportionately affected by early-onset, high-grade malignancies. A fraction of this cancer health disparity can be explained by genetic differences between individuals of African or European descent. Here the wild-type Pro/Pro genotype at the TP53Pro72Arg (P72R) polymorphism (SNP:rs1042522) is more frequent in African Americans with cancer than in African Americans without cancer (51% vs 37%), and is associated with a significant increase in the rates of cancer diagnosis in African Americans. To test the hypothesis that p53 allele-specific gene expression may contribute to African American cancer disparities, p53 hemizygous knockout variants were generated and characterized in the RKO colon carcinoma cell line, which is wild-type for p53 and heterozygous at theTP53Pro72Arg locus. Transcriptome profiling, using RNAseq, in response to the DNA-damaging agent etoposide revealed a large number of p53-regulated transcripts, but also a subset of transcripts that were ...

So far, we have discussed genes which have only two alleles. However, that is not always the case: there can be more than two alleles for a given gene. One example is the MITF gene, which is the major gene that controls white spotting in dogs. This protein is required for the migration and survival of melanocytes into the skin during development. If it is not functional, it impairs the ability of the skin to make pigment, thus covering up the effect of other color genes. There are thought to be at least four alleles that can contribute (Karlsson, 2007). Depending on which alleles are present in a dog, the amount of white can vary from none (a solid-colored dog) to mostly white (Table 2 and Figure 24).. Table 2: Combinations of different alleles for MITF result in different amounts of white present in the coat.. ...

Genetics Problems Abo Multiple Allele Abo Multiple Allele Worksheet worksheets 6th grade algebra games free kumon worksheets for kindergarten lcm math games homework hotline skillsworkshop math Even the youngest students-kindergarteners-will benefit from printable worksheets. They will help your little one learn and master basic concepts in way that will capture and hold their attention. Remember that small kids enjoy doing things rather than simply reading or listening. For this reason, attractive, well-illustrated worksheets with something to do will make learning fun for them. Whats more, completing your worksheet will give the child a tremendous sense of fulfillment. Remember to select worksheets that are the right level difficulty for your child. Get something too hard, and your child will become discouraged. Make it too easy, and they wont learn much. Homeschool worksheets are far more than busy work. They are an important part of making sure that the concepts you teach in your home school

Genes and factors are the same thingsâ ¦ Actually the word factor was given by mendal to genes.. A gene is a unit of hereditary information. ... while the genome surrounds the set of genes contained in a chromosome. Genes can have two or more possible alleles. Lv 6. Genes â ¦ Except in some viruses, genes are made up of DNA, a complex molecule that codes genetic information for the transmission of inherited traits. Source(s): lotion. The key difference between allele and genotype is that the allele is one of the variant forms of a gene located at the same genetic locus of a chromosome while genotype is the genetic constitution of a particular trait.. Genetics is the study of genes and hereditary patterns in organisms. mutation. Chromosome: Chromosomal â ¦ Mutation influence. As nouns the difference between allele and haplotype is that allele is (genetics) one of a number of alternative forms of the same gene occupying a given position on a chromosome while haplotype is (genetics) a group ...

The hTERT (human telomerase reverse transcriptase) gene contains five variable number tandem repeats (VNTR) and previous studies have described polymorphisms for hTERT-VNTR2-2nd. We investigated how allelic variation in hTERT-VNTR2-2nd may affect susceptibility to prostate cancer. A case-control study was performed using DNA from 421 cancer-free male controls and 329 patients with prostate cancer. In addition, to determine whether the VNTR polymorphisms have a functional consequence, we examined the transcriptional levels of a reporter gene linked to these VNTRs and driven by the hTERT promoter in cell lines. Three new rare alleles were detected from this study, two of which were identified only in cancer subjects. A statistically significant association between rare hTERT-VNTR2-2nd alleles and risk of prostate cancer was observed [OR, 5.17; 95% confidence interval (CI), 1.09-24.43; P = 0.021]. Furthermore, the results indicated that these VNTRs inserted in the enhancer region could influence the

TY - JOUR. T1 - Allele frequency heterogeneity in the collaborative study on the genetics of alcoholism (COGA). AU - Saccone, N. L.. AU - Rice, J. P.. AU - Goate, A.. AU - Conneally, P. M.. AU - Edenberg, H.. AU - Foroud, T.. AU - Nurnberger, J.. AU - Reich, T.. PY - 2000/8/7. Y1 - 2000/8/7. N2 - It is well known that admixture of populations having different marker allele frequencies can increase type I error in genome scans with ungenotyped parents, and can cause spurious association in case/control association studies of candidate genes. The Collaborative Study on the Genetics of Alcoholism has ascertained multiplex case families through alcoholic probands. Using markers from a genome screen, we compared allele frequencies among racial groups and found significant and extensive heterogeneity in the COGA data. Differences were also observed at candidate loci commonly studied for association with psychiatric disorders. A total of 609 genotyped founders from COGA case families have identified a ...

Previously, we found marked age-dependent changes in the occurrence of the C4B*Q0 allele in healthy people: the frequency of the allele was found to drop with increasing age. Frequency values were 0.161 and 0.054 in 252 healthy subjects aged ,45 years and 485 healthy subjects aged ,60 years, respectively.18 To explain this dramatic change, we have assumed that the C4B*Q0 allele is a negative selection factor for health and survival: carriers of C4B*Q0 are continuously selected from the healthy population because of their increased susceptibility for life-threatening and/or chronic diseases.18 The leading cause of death in Hungary, as in many other parts of the developed world, is CHD and its consequence, myocardial infarction. In populations of Hungary and Iceland, we have obtained much evidence indicating that the morbidity in CHD and myocardial infarction is significantly higher in C4B*Q0 carriers than in noncarriers.9 10 The difference in frequency between these patients and age-matched ...

The unstable equilibrium associated with underdominance provides a reversibly means by which transgenes can be pushed through a population. This equilibrium is quickly shifted when one of the allele frequencies surpasses a critical threshold value (usually by transgene release). When the frequency of the transgene allele is above the threshold compared to the wild type allele then the mutant allele will push through the population and become fixed. The converse is true for wild type alleles, meaning that underdominant systems are bi-directional. An attractive feature of underdominance systems as a tool for introducing transgenes into natural populations is their intrinsic reversibility. Allelic frequencies can be shifted in favor of the transgene for a given time and then returned to wild type should the necessity arise.. Similar to any other gene drive mechanisms, allele frequency, fitness cost, and system stability (keep effector genes linked to the driving alleles) are great concerns with ...

Author Summary Natural allelic variability is crucial for genetic improvement. While the genetic mechanisms leading to such variation have been studied in depth, relatively less is known about the role of epigenetic mechanisms in generation of allelic diversity. Paramutation is a phenomenon in which one allele can silence another allele in trans and, once established, such epigenetic silencing is heritable. To further understand the molecular components of paramutation, we characterized two epialleles of the pericarp color1 (p1) gene of maize, which originated from a common progenitor; however, only one of these alleles is paramutagenic. Results show that, while both alleles have high levels of symmetric (CG and CHG) methylation in a distal enhancer element, only the paramutagenic allele has higher levels of asymmetric (CHH) methylation. Since CHH methylation is imposed and maintained through RNA-mediated mechanisms, these results indicate that paramutation at the p1 locus involves RNA-mediated

In epigenetics, a paramutation is an interaction between two alleles at a single locus, whereby one allele induces a heritable change in the other allele. The change may be in the pattern of DNA methylation or histone modifications. The allele inducing the change is said to be paramutagenic, while the allele that has been epigenetically altered is termed paramutable. A paramutable allele may have altered levels of gene expression, which may continue in offspring which inherit that allele, even though the paramutagenic allele may no longer be present. Through proper breeding, paramutation can result in sibling plants that have the same genetic sequence, but with drastically different phenotypes. Though studied primarily in maize, paramutation has been described in a number of other systems, including animal systems like Drosophila melanogaster and mice. Despite its broad distribution, examples of this phenomenon are scarce and its mechanism is not fully understood. The first description of what ...

Gene conversion is an outcome of recombination, causing non-reciprocal transfer of a DNA fragment. Several decades later than the discovery of crossing over, gene conversion was first recognized in fungi when non-Mendelian allelic distortion was observed. Gene conversion occurs when a double-strand break is repaired by using homologous sequences in the genome. In meiosis, there is a strong preference to use the orthologous region (allelic gene conversion), which causes non-Mendelian allelic distortion, but paralogous or duplicated regions can also be used for the repair (inter-locus gene conversion, also referred to as non-allelic and ectopic gene conversion). The focus of this special issue is the latter, interlocus gene conversion; the rate is lower than allelic gene conversion but it has more impact on phenotype because more drastic changes in DNA sequence are involved. [...]

The genes of the major histocompatibility complex are the most polymorphic genes in vertebrates, with more than 1,000 alleles described in human populations. How this polymorphism is maintained, however, remains an evolutionary puzzle. Major histocompatibility complex genes have a crucial function in the adaptive immune system by presenting parasite-derived antigens to T lymphocytes. Because of this function, varying parasite-mediated selection has been proposed as a major evolutionary force for maintaining major histocompatibility complex polymorphism. A necessary prerequisite of such a balancing selection process is rapid major histocompatibility complex allele frequency shifts resulting from emerging selection by a specific parasite. Here we show in six experimental populations of sticklebacks, each exposed to one of two different parasites, that only those major histocompatibility complex alleles providing resistance to the respective specific parasite increased in frequency in the next host ...

1 . Microsatellite-based genetic assignment is used broadly to monitor contemporary effective dispersal among populations. The need to investigate the robustness of this method to common genotyping errors was emphasized more than a decade ago, but it remains unaddressed. 2 . We evaluate here for the first time the effect of mistaken and null alleles on estimates of contemporary seed and pollen migration rates obtained with genetic assignment methods. We also introduce a novel Bayesian approach to jointly estimate seed and pollen migration rates, genotyping error rates and null allele frequencies, not requiring independent reference or duplicate genotypic data. 3 . Unaccounted-for mistaken alleles caused positive bias and increased the root mean square error (RMSE) of pollen migration rate estimates, whereas seed migration rate estimates were weakly sensitive to mistyping. Jointly estimating mistyping rates minimized the bias and RMSE they introduce on pollen migration estimates, while yielding ...

Lithuim: Dominant traits arent preferentially passed along between generations, they just express more strongly if they are passed down.. If a dominant gene is rare, it may continue to be rare unless theres some selective pressure killing off animals without it.. whythecynic: Dominant and recessive simply describe how two *alleles* interact with each other. A dominant allele may be *disadvantageous*- in which case it would slowly die out. It might simply be rarer- when most of the population has recessive alleles, the dominant allele doesnt increase in number as quickly.. Thats the simple description- lets look at it closely!. ## Alleles. The DNA of humans (like most animals) is paired up. We have two copies of each gene. Each copy doesnt have to be the same, too, and we can have two different versions of the same gene.. Each version of a gene is called an *allele*.. ## Dominance. When an allele is *dominant*, the organism takes on that trait even if it has another *recessive* allele. ...

Heterozygote advantage is the superior fitness often seen in hybrids, the cross between two dissimilar parents. A heterozygote is an organism with two different alleles, one donated from each parent. Fitness means the ability to survive and have offspring. Heterozygote advantage also refers more narrowly to superior fitness of an organism that is heterozygous for a particular gene, usually one governing a disease.. Inbreeding is the practice of repeatedly crossing a single variety of organism with itself, in order to develop a more uniform variety. During this process, the organism becomes homozygous for many genes, meaning that its two gene copies are identical. This is often accompanied by loss of vigor: slower growth, less resistance to disease, and other signs of decreased fitness. This is known as inbreeding depression. Breeding with another variety (outcrossing) produces offspring that are heterozygous for many genes, and is often accompanied by an increase in size and vigor. This ...

OBJECTIVES: To identify the functional basis for the genetic association of single nucleotide polymorphisms (SNP), upstream of the RUNX3 promoter, with ankylosing spondylitis (AS). METHODS: We performed conditional analysis of genetic association data and used ENCODE data on chromatin remodelling and transcription factor (TF) binding sites to identify the primary AS-associated regulatory SNP in the RUNX3 region. The functional effects of this SNP were tested in luciferase reporter assays. Its effects on TF binding were investigated by electrophoretic mobility gel shift assays and chromatin immunoprecipitation. RUNX3 mRNA levels were compared in primary CD8+ T cells of AS risk and protective genotypes by real-time PCR. RESULTS: The association of the RUNX3 SNP rs4648889 with AS (p|7.6×10(-14)) was robust to conditioning on all other SNPs in this region. We identified a 2 kb putative regulatory element, upstream of RUNX3, containing rs4648889. In reporter gene constructs, the protective rs4648889 G

An allele is a form of a gene at a particular position (locus) on a chromosome.[1]15 It is the bit of coding DNA at that place.[2]p6 Typical plants and animals have two sets of chromosomes, one set inherited from each parent.[1]123 These organisms are called diploid. Since such organisms have two sets of chromosomes, they have (except on the sex chromosomes) two alleles at each gene locus.[2]p6 If the two alleles are identical, the individual is called a homozygote and is said to be homozygous. If instead the two alleles are different, the individual is a heterozygote and is heterozygous.[1]205 ...

The difference between short and long hair in dogs is caused by different alleles of a gene called FGF5. This gene produces a protein that is important in regulating the hair growth cycle. When the protein doesnt function correctly, the growth phase of the hair cycle is longer, resulting in long hair. Short hair is the dominant trait. Since Sugar has short hair, we know she has at least one dominant allele of FGF5. We can use the letter S for short hair. Sugars genotype for FGF5 is therefore S-, meaning she has one dominant allele and we cant tell by looking at her what her second allele is.. Sugars hair is also straight, which means that she has two straight alleles of KRT71. Her genotype would be K+K+.. Sugar is more than 50% white with irregular splashes of color, which means that her genotype for MITF (the gene that controls white spotting) is sise.. The brindle pattern is caused by the kbr allele at the K locus. Sugar cant have the KB allele or she would have solid color instead of ...

All (sexually reproducing) organisms contain their genetic information in paired form. Each offspring inherits half its genetic information from its mother, and half from its father. So there are two genes at a given position (locus, plural loci) coding for a particular characteristic. An organism can be heterozygous at a given locus, meaning it carries different forms (alleles) of this gene. For example, one allele can code for blue eyes, while the other one can code for brown eyes; or one can code for the A blood type and the other for the B type. Sometimes two alleles have a combined effect, while at other times only one allele (called dominant) has any effect on the organism, while the other does not (recessive). With humans, both the mothers and fathers halves have 100,000 genes, the information equivalent to a thousand 500-page books (3 billion base pairs, as Teaching about Evolution correctly states on page 42). The ardent neo-Darwinist Francisco Ayala points out that humans today have ...

Im not finding time to give these papers a full post each, so let me pool together several in the same theme: MHC alleles and protection against pathogens.. Its generally accepted that the reason there are so many MHC alleles is related to their ability to protect against pathogens.1 The version is probably the frequency-dependent selection model. According to this, pathogens are selected to be resistant to common MHC alleles, so individuals with rare alleles have a selective advantage and those alleles become more common, until pathogens are selected for resistance to them in turn. (Described in more detail here.).. The particular steps in this concept are each fairly straightforward and reasonably well supported. We know that different MHC alleles can be more or less effective against pathogens; we see some instances of pathogens developing resistance to particular MHC alleles, and so on. But its been quite difficult to put all the pieces together. The best examples of pathogens evolving ...

Alzheimers disease is a progressive brain disorder characterized initially by memory loss and later by the loss of thinking, reasoning and behavioural abilities. There are both early-onset and late-onset forms of Alzheimers disease. The late-onset form occurs in 90% of Alzheimers disease cases and the first symptoms generally appear after 65 years of age.. The APOE gene is the biggest genetic risk factor linked to the late-onset form of Alzheimers disease. The late-onset Alzheimers disease APOE genetic test determines the APOE alleles that an individual has inherited. These alleles indicate whether an individual has an increased lifetime risk of developing late-onset Alzheimers disease. To follow are all of the possible allele results and their associated risk:. Neutral (homozygous e3 / e3) A neutral result means that the person carries two copies of the APOE e3 allele. This is the most common allele and is a neutral allele, meaning there is no increased or decreased risk of Alzheimers ...

In allele DRB1*03:01, allele DRB1*03:02, allele DRB1*08:01, allele DRB1*08:02, allele DRB1*08:03, allele DRB1*08:04, allele DRB1*11:01, allele DRB1*11:04, allele DRB1*11:06, allele DRB1*11:11, allele DRB1*11:19, allele DRB1*12:01, allele DRB1*12:02, allele DRB1*13:01, allele DRB1*13:02, allele DRB1*13:03, allele DRB1*13:05, allele DRB1*13:07, allele DRB1*13:12, allele DRB1*14:01, allele DRB1*14:03, allele DRB1*14:05, allele DRB1*14:06 and allele DRB1*14:07 ...

Angiotensin I-converting enzyme (ACE), which plays an important role in blood pressure regulation, and methylenetetrahydrofolate reductase (MTHFR) involved in homocysteine metabolism belong to a large group of polypeptides which may be potential risk factors for atherosclerosis and coronary artery disease (CAD). To assess whether polymorphisms of the genes encoding these peptides are associated with CAD in Silesian we conducted a study among 68 individuals suffering from CAD (including 52 cases after myocardial infarction), 51 subjects with positive family history of CAD and 111 controls. We analysed the distribution of genotypes and allele frequencies of the insertion/deletion (I/D) polymorphism in the ACE gene using PCR amplification, and the C677→T polymorphism in the MTHFR gene using PCR-RFLP analysis. We found that D allele frequency was significantly higher in CAD patients (61%) than in controls (43%) (P = 0.001, OR = 2.06). The D allele carriers (DD + ID genotypes) were more frequent in ...

Looking for online definition of recessive allele in the Medical Dictionary? recessive allele explanation free. What is recessive allele? Meaning of recessive allele medical term. What does recessive allele mean?

The effective population size (Ne) is a major factor determining allele frequency changes in natural and experimental populations. Temporal methods provide a powerful and simple approach to estimate short-term Ne. They use allele frequency shifts between temporal samples to calculate the standardized variance, which is directly related to Ne. Here we focus on experimental evolution studies that often rely on repeated sequencing of samples in pools (Pool-seq). Pool-seq is cost-effective and often outperforms individual-based sequencing in estimating allele frequencies, but it is associated with atypical sampling properties: Additional to sampling individuals, sequencing DNA in pools leads to a second round of sampling, which increases the variance of allele frequency estimates. We propose a new estimator of Ne, which relies on allele frequency changes in temporal data and corrects for the variance in both sampling steps. In simulations, we obtain accurate Ne estimates, as long as the drift ...

The recent genome-wide allele-specific copy number variation data enable us to explore two types of genomic information including chromosomal genotype variations as well as DNA copy number variations. For a cancer study, it is common to collect data for paired normal and tumor samples. Then, two types of paired data can be obtained to study a disease subject. However, there is a lack of methods for a simultaneous analysis of these four sequences of data. In this study, we propose a statistical framework based on the change-point analysis approach. The validity and usefulness of our proposed statistical framework are demonstrated through the simulation studies and applications based on an experimental data set.

TY - JOUR. T1 - Preferential loss of maternal alleles in sporadic Wilms tumour. AU - Pal, N.. AU - Wadey, R. B.. AU - Buckle, B.. AU - Yeomans, E.. AU - Pritchard, J.. AU - Cowell, J. K.. PY - 1990. Y1 - 1990. N2 - Loss of heterozygosity at loci on the short arm of chromosome 11 has been reported in 31% (11/38) of Wilms tumours in our series. Lymphoblastoid cell lines were prepared from the parents of 10/11 of the patients showing allele loss in their tumours. In 9 of the cases, where the parental origin of the alleles could be followed, it was the paternal alleles which were retained in the tumour. This preferential loss of the maternal alleles implies a role for genomic imprinting in the pathogenesis of Wilms tumour.. AB - Loss of heterozygosity at loci on the short arm of chromosome 11 has been reported in 31% (11/38) of Wilms tumours in our series. Lymphoblastoid cell lines were prepared from the parents of 10/11 of the patients showing allele loss in their tumours. In 9 of the cases, ...

A Deleterious Allele is an allele (gene variant) that has the effect of reducing an organisms Darwinian fitness relative to an allele that is not deleterious (i.e., which could be a neutral allele, more so a beneficial allele, or less so a less deleterious allele). ...

In Saccharomyces cerevisiae, Rad59 is required for multiple homologous recombination mechanisms and viability in DNA replication-defective rad27 mutant cells. Recently, four rad59 missense alleles were found to have distinct effects on homologous recombination that are consistent with separation-of-function mutations. The rad59-K166A allele alters an amino acid in a conserved α-helical domain, and, like the rad59 null allele diminishes association of Rad52 with double-strand breaks. The rad59-K174A and rad59-F180A alleles alter amino acids in the same domain and have genetically similar effects on homologous recombination. The rad59-Y92A allele alters a conserved amino acid in a separate domain, has genetically distinct effects on homologous recombination, and does not diminish association of Rad52 with double-strand breaks. In this study, rad59 mutant strains were crossed with a rad27 null mutant to examine the effects of the rad59 alleles on the link between viability, growth and the stimulation of

The single nucleotide polymorphism (SNP) rs1053004 in Signal transducer and activator of transcription 3(STAT3) was recently reported to be associated with chronic hepatitis B (CHB)-related hepatocellular carcinoma(HCC) in a Chinese cohort. This study was aimed at investigating whether the SNP might also contribute toHCC susceptibility in the Thai population. Study subjects were enrolled and divided into 3 groups includingCHB-related HCC (n=211), CHB without HCC (n=233) and healthy controls (n=206). The SNP was genotypedusing allelic discrimination assays based on TaqMan real-time PCR. Data analysis revealed that the distributionof different genotypes was in Hardy-Weinberg equilibrium (P|0.05). The frequencies of allele T (major allele)in HCC patients, CHB patients and healthy controls were 51.4%, 58.6% and 61.4%, respectively, whereas thefrequencies of C allele (minor allele) were 48.6%, 41.4% and 38.6%. The C allele frequency was higher in HCCwhen compared with CHB patients (odds ratio (OR)=1.34, 95%

Approach and Results-The LPA null allele (rs41272114) was genotyped in the PROCARDIS case-control cohort (4073 CAD cases and 4225 controls). Lipoprotein(a) levels were measured in 909 CAD cases and 922 controls; apolipoprotein(a) isoform size was estimated using sodium dodecyl sulfate-agarose gel electrophoresis and a high-throughput quantitative polymerase chain reaction-based method. Null carriers are common (null allele frequency, 3%) and have significantly lower circulating lipoprotein(a) levels (P=2.1×10−10) and reduced CAD risk (odds ratio, 0.79 [0.66-0.97]; P=0.023) compared with noncarriers. An additive allelic model of apolipoprotein(a) isoform size, refined by null allele genotype and quantitative polymerase chain reaction values, showed a sigmoid relationship with lipoprotein(a) levels, with baseline levels for longer isoform alleles and progressively higher levels of lipoprotein(a) for shorter isoform alleles.. ...

The AmpliChip CYP450 analysis was performed on the same patient samples as the Invader copy number FRET analysis. The AmpliChip assay was able to provide both confirmation of the gene dosage as indicated by the FRET assay and a more detailed analysis of the exact polymorphisms each patient possessed. Table 3lists the gene frequency in the study population. All patients demonstrating a 1× signal on the FRET analysis were shown to carry the CYP2D6*5 gene deletion allele on the AmpliChip assay (100% concordance). This finding is consistent with the design of the Invader copy number test, which does not recognize or bind to the CYP2D6*5 allele. The presence of CYP2D6*5 is therefore inferred from the 1× signal in a compound heterozygote (where one of the alleles is CYP2D6*5). The AmpliChip CYP450 assay further allowed us to clarify the status of those patients designated as 2× by indicating the presence of nonfunctioning and reduced activity alleles other than CYP2D6*5. Using the AmpliChip data, ...

Accuracy of genotyping of single-nucleotide polymorphisms by PCR-ELISA allele-specific oligonucleotide hybridization typing and by amplification refractory mutation ...

DUGi: Viewing Item from repository Recercat: Delta-like 1 homolog (DLK1) gene encodes a transmembrane protein containing epidermal growth factor-like repeats that promotes the induction of mesenchymal cells but prevents chondrocyte, preadipocytes and osteoblast maturation and differentiation. Rs1802710 polymorphism situated in the fifth exon of DLK1, shows a significant parent-of-origin effect reflecting the known silencing of the maternally inherited copy by imprinting. In humans, a more frequent paternal transmission of the paternal allele in the rs1802710 polymorphism of DLK1 on obese children has been noticed. We aimed to study the single nucleotide polymorphism (SNP) rs1802710 of the DLK1 gene and its effects on early life development. Due to the known imprinting effect surrounding the DLK1 locus, we wanted to analyze whether these changes were different depending on the parental origin of the transmitted rs1802710 variant T allele. Therefore, a longitudinal study has been done from the beginning

Interindividual and interethnic differences in allele frequencies of N-acetyltransferase (NAT2) single nucleotide polymorphisms (SNPs) are responsible for phenotypic variability of adverse drug reactions and susceptibility to cancer. We genotyped the seven NAT2 common SNPs in 127 randomly selected unrelated northern Sudanese subjects using allele-specific and RFLP polymerase chain reaction (PCR) based methods. Molecular genotyping was enough to designate alleles for 41 individuals unambiguously, whereas 63 individuals alleles were inferred from haplotypes previously described. In the remaining 23 individuals, however, the phase of the SNPs could not be decided because of multiple SNP heterozygotes. Using computational methods in the HAP and Phase programs, we confirmed the inferred alleles of the 62 individuals and predicted the remaining 23 ambiguous alleles. Twelve NAT2 alleles were identified. Four alleles coded for rapid acetylators (18%), and eight alleles coded for slow acetylators (82%). Two

The cation-independent mannose 6-phosphate/insulin-like growth factor-2 receptor (M6P/IGF2R or IGF2R) traffics IGF2 and M6P ligands between pre-lysosomal and extra-cellular compartments. Specific IGF2 and M6P high-affinity binding occurs via domain-11 and domains-3-5-9, respectively. Mammalian maternal Igf2r allele expression exceeds the paternal allele due to imprinting (silencing). Igf2r null-allele maternal transmission results in placenta and heart over-growth and perinatal lethality (|90%) due to raised extra-cellular IGF2 secondary to impaired ligand clearance. It remains unknown if the phenotype is due to either ligand alone, or to both ligands. Here, we evaluate Igf2r specific loss-of-function of the domain-11 IGF2 binding site by replacing isoleucine with alanine in the CD loop (exon 34, I1565A), a mutation also detected in cancers. Igf2rI1565A/+p maternal transmission (heterozygote), resulted in placental and embryonic over-growth with reduced neonatal lethality (|60%), and long-term survival.

I am sorry to say that your parents may have misunderstood the genetic explaination of the disease. A recessive allele never takes over a dominant allele. Cerebral Palsy, however, is mostly caused by infection, stroke (due to many rasons, such as abnormal blood cells),oxygen loss during pregnancy or child birth, jaundice, and Rh incompatibility. Thus Cerebral palsy seems to have no direct genetic component, however there can be an indirect genetic component such as the abnormal blood cells mentioned above. To talk about Anglemens Syndrome: Genetic imprinting- Differential modification of the expression of genes depending upon whether they are inherited from the mother or the father. This affects only certain segments of the human genetic complement,including PWS (Prader-willi Syndrome, see below) and Angelman syndrome on chromosome 15q. Anglemens Syndrome- A rare syndrome reported in 1965 by Dr. H. Angelman and associated with a chromosome 15 deletion similar to that seen in PWS. In AS, ...

Author(s): Smit-McBride, Z; Moya, A; Ayala, FJ | Abstract: We have studied linkage disequilibrium in Drosophila melanogaster in two samples from a wild population and in four large laboratory populations derived from the wild samples. We have assayed four polymorphic enzyme loci, fairly closely linked in the third chromosome: Sod Est-6, Pgm, and Odh. The assay method used allows us to identify the allele associations separately in each of the two homologous chromosomes from each male sampled. We have detected significant linkage disequilibrium between two loci in 16.7% of the cases in the wild samples and in 27.8% of the cases in the experimental populations, considerably more than would be expected by chance alone. We have also found three-locus disequilibria in more instances than would be expected by chance. Some disequilibria present in the wild samples disappear in the experimental populations derived from them, but new ones appear over the generations. The effective population sizes required to

Looking for online definition of modification allele in the Medical Dictionary? modification allele explanation free. What is modification allele? Meaning of modification allele medical term. What does modification allele mean?

Autosomal dominant inheritance is due to a dominant allele carried on one of the autosomes. Autosomal dominant alleles need only be inherited from one parent, either the mother or the father, in order to be expressed in the phenotype. Because of this, any child has a 50 percent chance of inheriting the allele and expressing the trait if one parent has it.. Many normal human traits are due to autosomal dominant alleles, including the presence of dimples, a cleft chin, and a widows-peak hairline. Note that dominant does not necessarily mean common. Dominant alleles can be rare in a population, and do not spread simply because they are dominant. This phenomenon is explained by the theory known as Hardy-Weinberg equilibrium.. There are hundreds of medical conditions due to autosomal dominant alleles, most of them very rare. They include neurodegenerative disorders such as Huntingtons disease, a variety of deafness syndromes, and metabolic disorders such as familial hypercholesterolemia (affecting ...

BACKGROUND: There is evidence that iron may play a role in the pathology of Alzheimers disease (AD). There may be genetic factors that contribute to iron deposition resulting in tissue damage thus exacerbating AD. METHODS: We have genotyped 269 healthy elderly controls, 191 cases with definite or probable AD, and 69 with mild cognitive impairment (MCI) from the OPTIMA cohort. RESULTS: We have examined the interaction between the C2 variant of the transferrin (TF) gene and the C282Y allele of the haemochromatosis (HFE) gene as risk factors for developing AD. Our results showed that each of the two variants was associated with an increased risk of AD only in the presence of the other. Neither allele alone had any effect. Carriers of both variants were at 5 times greater risk of AD compared with all others. The interaction was significant by logistic regression (p = 0.014) and by synergy factor analysis (p = 0.015, synergy factor = 5.1). Further, carriers of these two alleles plus apolipoprotein E

When a previously stable population undergoes inbreeding, if nothing else changes, natural selection should consist mainly of purging. The joint consequences of inbreeding and purging on fitness vary depending on many factors: the previous history of the population, the rate of increase of inbreeding, the harshness of the environment or of the competitive conditions, etc. The effects of purging were first noted by Darwin[10] in plants, and have been detected in laboratory experiments and in vertebrate populations undergoing inbreeding in zoos or in the wild, as well as in humans.[11] The detection of purging is often obscured by many factors, but there is consistent evidence that, in agreement with the predictions explained above, slow inbreeding results in more efficient purging, so that a given inbreeding F leads to less threat to population viability if it has been produced more slowly.[12] Nevertheless, in practical situations, the genetic change in fitness also depends on many other ...

To the Editor:. Nakayama et al1 have described an interesting polymorphism in the NPR-A gene in a Japanese population. An 8-nucleotide deletion in the 5′ untranslated region (UTR) of the gene was found to be associated with essential hypertension and left ventricular hypertrophy in a study of 200 hypertensive (HT) and 200 normotensive (NT) subjects. The polymorphism occurred at a frequency of 4% in the HT patients and in a single NT subject (0.5%) who was subsequently found to have left ventricular hypertrophy. Carriers of the functional deletion (D) allele had higher plasma BNP levels, a strong marker of cardiac stress, than those with the wild-type allele. Expression of NPR-A from the D allele was reduced compared with the wild-type allele and it is suggested that the deletion interferes with binding of regulatory factors to the 5′ UTR of the gene.1. We screened 498 patients from the Christchurch Post-Myocardial Infarction (PMI) Study2-4 who had acute myocardial infarction for the NPR-A D ...

We analyzed 100 control individuals and 60 patients with psoriasis vulgaris from the population of Campinas, Brazil. Typification of class II HLA alleles (HLA-DRB1-5 and -DQB1) was carried out through the DNA/PCR/SSP at medium and high resolution. DNA was extracted through a salting-out procedure: 13 DRB1 alleles, 3 DRB3 alleles, 1 DRB4 allele, 2 DRB5 alleles, and 5 DQB1 alleles were identified at a medium resolution using the PCR/SSP, and 45 DRB1 alleles were identified at a high resolution in analyzed patients. Results showed associations with psoriasis vulgaris: positive associations HLA-DRB3*02 (p , 0.05, chi(2) = 5.10, RR = 2.14); HLA-DRB1*0102 alleles (p , 0.05, RR = 5.44). Negative associations were found for HLA-DRB4*01 (chi(2) = 3.23, RR = 0.55) and HLA-DRB1*1302 alleles (p , 0.05, RR = 0.23). The haplotypes revealed positive association for HLA-DRB1*0102/DQB1*05 (p , 0.05, RR = 5.44) and HLA-DRB1*0701/DQB1*03 alleles (p , 0.02, RR = 9.00). These findings suggest a possible association ...

TY - JOUR. T1 - Gene-behavior interaction of depressive symptoms and the apolipoprotein e ε4 allele on cognitive decline. AU - Rajan, Kumar. AU - Wilson, Robert S.. AU - Skarupski, Kimberly A.. AU - Mendes De Leon, Carlos F.. AU - Evans, Denis A.. PY - 2014/1/1. Y1 - 2014/1/1. N2 - Objective: Depressive symptoms and the apolipoprotein E (APOE) [Latin Small Letter Open ε4 allele are independent risk factors for cognitive decline. However, it is not clear whether the presence of both depressive symptoms and the APOE [Latin Small Letter Open ε4 allele increases cognitive decline. METHODS: A prospective study of a population-based sample of 4150 (70% African American and 63% women) participants 65 years and older who were interviewed at 3-year intervals was conducted. Depressive symptoms were measured using the 10-item version of the Center for Epidemiologic Studies Depression scale, with each item coded as presence or absence of a symptom. The APOE genotype was ascertained by DNA samples ...

This track contains information about a subset of the single nucleotide polymorphisms and small insertions and deletions (indels) - collectively Simple Nucleotide Polymorphisms - from dbSNP build 142, available from ftp.ncbi.nih.gov/snp. Only SNPs flagged as clinically associated by dbSNP, mapped to a single location in the reference genome assembly, and not known to have a minor allele frequency of at least 1%, are included in this subset. Frequency data are not available for all SNPs, so this subset probably includes some SNPs whose true minor allele frequency is 1% or greater. Note: The original version of this track contained incorrect allele frequencies for approximately 1% of all variants in dbSNP build 142; specifically, variants submitted by the 1000 Genomes Project and mapped to the reverse (-) strand of the genome. In November 2015, we released an update that removed the incorrect allele frequency data so the affected variants now have no allele frequency data. The significance of any ...

Impaired neuronal migration and cell death are commonly observed in patients with peroxisomal biogenesis disorders (PBDs), and in mouse models of this diseases. In Pex11β-deficient mice, we observed that the deletion of a single allele of the Pex11β gene (Pex11β+/− heterozygous mice) caused cell death in primary neuronal cultures prepared from the neocortex and cerebellum, although to a lesser extent as compared with the homozygous-null animals (Pex11β−/− mice). In corresponding brain sections, cell death was rare, but differences between the genotypes were similar to those found in vitro. Because PEX11β has been implicated in peroxisomal proliferation, we searched for alterations in peroxisomal abundance in the brain of heterozygous and homozygous Pex11β-null mice compared with wild-type animals. Deletion of one allele of the Pex11β gene slightly increased the abundance of peroxisomes, whereas the deletion of both alleles caused a 30% reduction in peroxisome number. The size of the ...

To understand the biological mechanism of ELL2 in multiple myeloma (MM), we show that the MM risk allele lowers ELL2 expression in CD138+ plasma cells (Pcombined=2.5×10-27; bcombined=-0.24 s.d.), but not in peripheral blood or other tissues. Consistent with this, several variants representing the MM risk allele map to regulatory genomic regions, and three yield reduced transcriptional activity in plasmocytoma cell lines. One of these (rs3777189-C) co-locates with the best-supported lead variants for ELL2 expression and MM risk, and reduces binding of MAFF/G/K family transcription factors. Moreover, further analysis reveals that the MM risk allele associates with upregulation of gene sets related to ribosome biogenesis, and knockout/knockdown and rescue experiments in plasmocytoma cell lines support a cause-effect relationship.

Human immunodeficiency virus (HIV)-1 amino acid sequence polymorphisms associated with expression of specific human histocompatibility leukocyte antigen (HLA) class I alleles suggest sites of cytotoxic T lymphocyte (CTL)-mediated selection pressure and immune escape. The associations most frequently observed are between expression of an HLA class I molecule and variation from the consensus sequence. However, a substantial number of sites have been identified in which particular HLA class I allele expression is associated with preservation of the consensus sequence. The mechanism behind this is so far unexplained. The current studies, focusing on two examples of negatively associated or apparently preserved epitopes, suggest an explanation for this phenomenon: negative associations can arise as a result of positive selection of an escape mutation, which is stable on transmission and therefore accumulates in the population to the point at which it defines the consensus sequence. Such negative ...

Objective: A case-control association study was conducted to determine HLA-class II (DRB1, DQB1, DQA1, and DPB1) alleles, haplotypes and shared epitopes associated with scleroderma (systemic sclerosis or SSc) and its sub-phenotypes in a large multi-ethnic US cohort.. Patients and methods: 1300 SSc cases (961 whites, 178 blacks and 161 Hispanics) characterized for clinical skin forms (limited vs diffuse), SSc- specific autoantibodies (anti-centromere (ACA), anti-topoisomerase I (ATA), anti-RNA polymerase III (ARA), anti-U3 RNP (fibrillarin), and others were studied using molecular genotyping. Statistical analyses in SSc itself by ethnicity, gender, skin type and autoantibodies were performed using exact logistic regression modeling for dominant (D), additive (A) and recessive (R) effects from HLA.. Results: The strongest positive class II associations with SSc in whites and Hispanics were the DRB1*1104, DQA1*0501, DQB1*0301 haplotype, and DQB1 alleles encoding a non-leucine residue at position 26 ...

HUMAN LEUKOCYTE ANTIGEN DR ALLELE 1 DONOR is the ORGAN OR TISSUE DONORs Human Leukocyte Antigen DR Allele 1, as contained in the Human Leukocyte Antigen report for Tissue Typing ...

The major findings of the present study are: (1) serum EPO levels of all individuals increased significantly 5-fold at week 4 and 14-fold at week 8 compared to baseline, (2) EPO rs1617640 G homozygotes showed significantly lower serum EPO levels during antiviral treatment compared to T allele carriers, (3) besides age, baseline Hb levels and RBV dose, EPO rs1617640 G allele is independently associated with Hb decline during antiviral treatment, (4) in EPO rs1617640 G homozygotes the need of RBV dose reduction as well as epoetin-α supplementation was signi ficantly higher compared to T allele carriers, (5) ITPA rs1127354 gene variant rather associated with Hb reduction at week 4 but not at week 12 and did not increase the risk of epoetin-α supplementation, RBV dose reduction or blood transfusion.. Hb decline during antiviral treatment is a frequent side effect and the reason for it is probably multifactorial. IFN-α induces a significant and rapid dose-dependent Hb decline in CHC patients ...

In the present study, DNA typing for human leucocyte antigen (HLA)-DPB1, -DRB1, and -DQB1 was performed using polymerase chain reaction-sequence-based-typing (PCR-SBT) method on 94 randomly selected, healthy, unrelated individuals from the Ewenki ethnic population in Inner Mongolia Autonomous Region of China. A total of 64 alleles: 25 in DRB1, 19 in DQB1 and 20 in DPB1, were found. Among the 25 detected DRB1 alleles, DRB1*090102, DRB1*030101, DRB1*040101, DRB1*070101, and DRB1*120101/1206 were commonly observed, with frequencies of 16.0%, 13.3%, 10.1%, 7.4%, and 7.4%, respectively. The most predominant DQB1 allele was DQB1*030101/0309 with the frequency of 27.7%, followed by DQB1*0201/0202 (19.7%), DQB1*030302 (12.8%), DQB1*060101/060103 (6.4%), and DQB1*050201 (5.9%). Of the 20 detected DPB1 alleles, DPB1*020102 was the most frequent allele with the frequency of 25.5%. DPB1*0402 (21.3%), DPB1*0401 (20.2%), DPB1*0501 (10.6%) and DPB1*4101 (3.7%) were also very frequent alleles. The most frequent ...

|jats:title|ABSTRACT|/jats:title| |jats:p|Despite the fact that the cell surface expression level of HLA-C on both uninfected and HIV-infected cells is lower than those of HLA-A and -B, increasing evidence suggests an important role for HLA-C and HLA-C-restricted CD8|jats:sup|+|/jats:sup| T cell responses in determining the efficiency of viral control in HIV-1-infected individuals. Nonetheless, HLA-C-restricted T cell responses are much less well studied than HLA-A/B-restricted ones, and relatively few optimal HIV-1 CD8|jats:sup|+|/jats:sup| T cell epitopes restricted by HLA-C alleles have been defined. Recent improvements in the sensitivity of mass spectrometry (MS)-based approaches for profiling the immunopeptidome present an opportunity for epitope discovery on a large scale. Here, we employed an MS-based immunopeptidomic strategy to characterize HIV-1 peptides presented by a protective allele, HLA-C*12:02. We identified a total of 10,799 unique 8- to 12-mer peptides, including 15 HIV-1 peptides. The

This track contains information about a subset of the single nucleotide polymorphisms and small insertions and deletions (indels) - collectively Simple Nucleotide Polymorphisms - from dbSNP build 142, available from ftp.ncbi.nih.gov/snp. Only SNPs that have a minor allele frequency of at least 1% and are mapped to a single location in the reference genome assembly are included in this subset. Frequency data are not available for all SNPs, so this subset is incomplete. Note: The original version of this track contained incorrect allele frequencies for approximately 1% of all variants in dbSNP build 142; specifically, variants submitted by the 1000 Genomes Project and mapped to the reverse (-) strand of the genome. In November 2015, we released an update that removed the incorrect allele frequency data so the affected variants now have no allele frequency data. The selection of SNPs with a minor allele frequency of 1% or greater is an attempt to identify variants that appear to be reasonably ...

This track contains information about a subset of the single nucleotide polymorphisms and small insertions and deletions (indels) - collectively Simple Nucleotide Polymorphisms - from dbSNP build 142, available from ftp.ncbi.nih.gov/snp. Only SNPs that have a minor allele frequency of at least 1% and are mapped to a single location in the reference genome assembly are included in this subset. Frequency data are not available for all SNPs, so this subset is incomplete. Note: The original version of this track contained incorrect allele frequencies for approximately 1% of all variants in dbSNP build 142; specifically, variants submitted by the 1000 Genomes Project and mapped to the reverse (-) strand of the genome. In November 2015, we released an update that removed the incorrect allele frequency data so the affected variants now have no allele frequency data. The selection of SNPs with a minor allele frequency of 1% or greater is an attempt to identify variants that appear to be reasonably ...

This track contains information about a subset of the single nucleotide polymorphisms and small insertions and deletions (indels) - collectively Simple Nucleotide Polymorphisms - from dbSNP build 142, available from ftp.ncbi.nih.gov/snp. Only SNPs that have a minor allele frequency of at least 1% and are mapped to a single location in the reference genome assembly are included in this subset. Frequency data are not available for all SNPs, so this subset is incomplete. Note: The original version of this track contained incorrect allele frequencies for approximately 1% of all variants in dbSNP build 142; specifically, variants submitted by the 1000 Genomes Project and mapped to the reverse (-) strand of the genome. In November 2015, we released an update that removed the incorrect allele frequency data so the affected variants now have no allele frequency data. The selection of SNPs with a minor allele frequency of 1% or greater is an attempt to identify variants that appear to be reasonably ...

This track contains information about a subset of the single nucleotide polymorphisms and small insertions and deletions (indels) - collectively Simple Nucleotide Polymorphisms - from dbSNP build 142, available from ftp.ncbi.nih.gov/snp. Only SNPs that have a minor allele frequency of at least 1% and are mapped to a single location in the reference genome assembly are included in this subset. Frequency data are not available for all SNPs, so this subset is incomplete. Note: The original version of this track contained incorrect allele frequencies for approximately 1% of all variants in dbSNP build 142; specifically, variants submitted by the 1000 Genomes Project and mapped to the reverse (-) strand of the genome. In November 2015, we released an update that removed the incorrect allele frequency data so the affected variants now have no allele frequency data. The selection of SNPs with a minor allele frequency of 1% or greater is an attempt to identify variants that appear to be reasonably ...

On the other hand single alleles would have spread randomly beyond the region of inbreeding. And the mutation may not even have originated in that region to start with. So, if the inbred population with the advantageous double allele were able to form hybrids with another population containing members with the single allele then the alleles expansion could become rapid. Especially considering that those with the double recessive allele would now have restored hybrid vigour. The population with restored hybrid vigour that carried the advantageous allele would be the one that expanded. Not the original inbred population. Presumably this method of allele expansion is a reasonably common pheneomenon. It certainly seems to explain our evolution right back to, and even beyond, Australopithecus. So hybrid vigour is just as important as inbreeding. ...

OBJECTIVES: In this study, we investigated whether polymorphisms of the HIF-1alpha gene may account for the patterns of HIF-1alpha protein expression in non-small cell lung carcinomas (NSCLC) and the expression of HIF-1alpha down-stream proteins. METHODS: Specific HIF-1alpha polymorphisms were assessed in a series of patients with NSCLC: (a) the C to T transition at nucleotide 1744 (position 2028 according to sequence with accession number , which gives rise to Pro/Ser variation at codon 582), (b) the G to A nucleotide substitution at point 1790 (position 2046 according to sequence with accession number , which gives rise to Ala/Thr variation at codon 588), and (c) the dinucleotide GT repeat polymorphism in intron 13. Immunohistochemistry for HIF-1alpha and down-stream proteins (VEGF, LDH-5, GLUT-1) was also performed in tumor material. RESULTS: A strong association of the P582S polymorphism and of GT repeat polymorphism higher than 14/14 with increased HIF-1alpha expression was noted. HIF-1alpha