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  • genome
  • This pattern was interpreted to reflect a history of introgressive hybridization from archaic hominins (most likely Asian Homo erectus ) into the anatomically modern human genome. (genetics.org)
  • A resequencing study of 2.4 kb of the ribonucleotide reductase M2 pseudogene 4 ( RRM2P4 ) in a sample of 41 globally diverse humans identified an unusual pattern of nucleotide polymorphism compared with most of the human genome. (genetics.org)
  • Genome sizes estimated from the total chromosome size demonstrate that TSC and CNI are 1.21 Gb and 1.29 Gb, respectively. (royalsocietypublishing.org)
  • Despite the large differences in genome size between these three species according to the database, GGA macrochromosomes, comprising about 70 per cent of the genome, show extensive homology in the karyotypes of TSC and CNI by chromosome painting [ 2 ]. (royalsocietypublishing.org)
  • Alternatively, genome size can be calculated from the sum of chromosome sizes determined by flow-karyotypic analysis using a flow cytometer [ 3 - 7 ]. (royalsocietypublishing.org)
  • Based on our more precise measurements, we find similar genome sizes in chicken, turtle and crocodile, and a relatively higher GC content in the smaller chromosomes of these three species. (royalsocietypublishing.org)
  • To provide markers to identify chromosomes in the genome of octopods, chromosomes of three octopus species were subjected to NOR /C-banding. (pensoft.net)
  • Current thinking, inspired by the results five years ago from the Human Genome Project, is that the 6 billion humans alive today are 99.9% similiar when it comes to genetic content and identity. (abc.net.au)
  • Until now, analysis of the genome has focused overwhelmingly on comparing differences, or polymorphisms, in the patterns of single letters in the chemical code for making and sustaining human life. (abc.net.au)
  • the clinical significance of human variation," say Professor Huntington Willard and Dr Kevin Shianna of the Institute for Genome Sciences and Policy at Duke University in North Carolina, in a review of the research. (abc.net.au)
  • This implies that, over the past 200,000 years or so, subtle variants have arisen in the genome to allow different populations of humans adapt to their different environments, according to scientists at Wellcome Trust Sanger. (abc.net.au)
  • genetic
  • In this study, we investigate patterns of genetic diversity in noncoding regions across the entire X chromosome of a global sample of 26 unrelated genetic females. (genetics.org)
  • Unfortunately, human DNA studies became the most contentious area of ancient DNA research, owing to the difficulties in discriminating authentic ancient DNA sequences from recent contamination [ 26 - 28 ], and many researchers concluded that human remains would not be amenable to genetic investigations. (royalsocietypublishing.org)
  • Because a large number of genetic and epigenetic alterations are required for a normal cell to become malignant, limiting the number of cellular divisions in human cells results in a preneoplastic proliferative growth arrest state referred to as senescence. (aacrjournals.org)
  • The researchers were astonished to locate 1447 CNVs in nearly 2900 genes, or around one eighth of the human genetic code. (abc.net.au)
  • telomere
  • Another intriguing possibility is that the human TERT gene may autoregulate itself, as it is located very close to the telomere end of chromosome 5. (aacrjournals.org)
  • Thus, when telomeres reach a certain length (∼15-20 kb) during human development, chromatin modifications involving telomere position effects may silence the TERT gene ( 3 ). (aacrjournals.org)
  • In humans with rare disorders of telomere maintenance (called telomeropathies), there is an early onset of diseases such as bone marrow failure, idiopathic pulmonary fibrosis, and dyskeratosis congenita (a disease showing age-associated tissue dysfunctions and a modest increase in cancer in highly proliferative tissues). (aacrjournals.org)
  • first tried to use fluorescence in situ hybridization on the cephalopod chromosomes and suggested that the telomere sequence of O. areolatus de Haan, 1839-1841 was (TTAGGG)n, but there was a lack of complete and clear metaphases in the report. (pensoft.net)
  • variation
  • One clade with very little sequence variation was specific to Asians, while the other more diverse clade of RRM2P4 sequences resembled a pattern typical of human variation and was globally distributed. (genetics.org)
  • Genetics and cytology combine to establish cytogenetics, mainly from the perspective of cytology, especially from a chromosome structure and function as well as the relationship between chromosomes and other organelles, to elucidate the mechanism of inheritance and variation. (pensoft.net)
  • significantly
  • The p mc summary statistic, which has improved power with larger samples of chromosomes, yields values that are significantly unlikely under the RAR model and fit expectations better under a range of archaic admixture scenarios. (genetics.org)
  • evolutionary
  • We define a new summary statistic called the minimum clade proportion ( p mc ), which quantifies the proportion of individuals from a specified geographic region in each of the two basal clades of a binary gene tree, and then employ coalescent simulations to assess the likelihood of the observed central RRM2P4 genealogy under two alternative views of human evolutionary history: recent African replacement (RAR) and archaic admixture (AA). (genetics.org)
  • To a large extent, these efforts were driven by the availability of well-preserved remains, for example megafauna preserved in permafrost, and the desire to broach phylogenetic and evolutionary questions without the formidable obstacles faced by human ancient DNA studies. (royalsocietypublishing.org)
  • analyses
  • In addition to the PAR1 and PAR2, there is a human-specific X-transposed region that was duplicated from the X to the Y. The X-transposed region is often not excluded from X-specific analyses, unlike the PARs, because it is not thought to routinely recombine. (genetics.org)
  • nucleotide
  • Map positions of single-nucleotide polymorphisms (SNPs) from replicated associations of chromosome 9p21 (Chr9p21) with cardiovascular disease traits ( top ) and SNPs identified by hypothesis-free GWASs for other diseases ( center ). (ahajournals.org)
  • long
  • The PAR1 spans the first 2.7 Mb of the proximal arm of the human sex chromosomes, while the much smaller PAR2 encompasses the distal 320 kb of the long arm of each sex chromosome. (genetics.org)
  • Interestingly, telomerase is more promiscuous in mice, and inbred strains of mice have very long telomeres compared with humans, but the reasons for this are not understood. (aacrjournals.org)
  • samples
  • For comparison, HSA (2 n = 46), GGA (2 n = 78), TSC (2 n = 50) and CNI (2 n = 32) chromosome samples were run on a flow cytometer (MoFlo, DAKO) separately but sequentially using the same settings. (royalsocietypublishing.org)
  • Studies
  • published one of the first studies to posit recent admixture between AMH and an archaic human population. (genetics.org)
  • However
  • however, the large variance associated with this estimate makes it difficult to distinguish the predictions of the human origins models tested here. (genetics.org)
  • However, crocodile chromosomes are different from those of birds and turtles that have numerous indistinguishable microchromosomes, and the chromosome GC content is unknown in CNI. (royalsocietypublishing.org)
  • common
  • A 2.4-kb stretch within the RRM2P4 region of the X chromosome, previously sequenced in a sample of 41 globally distributed humans, displayed both an ancient time to the most recent common ancestor ( e.g. , a TMRCA of ∼2 million years) and a basal clade composed entirely of Asian sequences. (genetics.org)
  • Brad Pitt has them, Paul Newman had them - but when it comes to the human population as a whole, blue eyes are not that common. (abc.net.au)
  • detection
  • The 1984 quagga article was followed shortly afterwards by a report of the detection of human DNA in an extract of muscle from a pre-Dynastic Egyptian mummy using DNA hybridization [ 8 ]. (royalsocietypublishing.org)
  • 16. Dyban A, Freidine M, Severova E, Cieslak J, Ivakhnenko V, Verlinsky Y. Detection of aneuploidy in human oocytes and corresponding first polar bodies by fluorescent in situ hybridization. (warwick.ac.uk)
  • researchers
  • The repercussions could be far-reaching for medical diagnosis, new drugs and the tale of human evolution itself, the researchers say. (abc.net.au)
  • cells
  • Almost all in situ preneoplastic lesions (sometimes referred to as indolent lesions of epithelial origin) have critically shortened telomeres, which may be an initial protective mechanism limiting the maximum number of divisions human cells can undergo. (aacrjournals.org)
  • large
  • By genotyping a diagnostic SNP in a large sample of humans, the divergent "Asian clade" was shown to be frequent in Southeast Asians and nearly absent in sub-Saharan Africans. (genetics.org)
  • It is also clear that superimposed on the maternal meiotic chromosome segregation errors, there are a large number of mitotic errors taking place post-zygotically during the first few cell divisions in the embryo. (warwick.ac.uk)
  • evolution
  • These cytogenetic characteristics will provide more theoretical foundation for further researches on chromosome evolution in octopods. (pensoft.net)
  • short
  • In crisis, telomeres are so short that end-to-end fusions occur, followed by bridge-breakage-fusion cycles, and only rarely in humans does a cell engage a mechanism to escape from crisis. (aacrjournals.org)
  • Mice with the Tert gene develop short telomeres and phenocopy many of the hallmarks of human aging after several generations. (aacrjournals.org)
  • gave
  • This gradient gave rise to the 'vitamin D hypothesis', which is the idea that light coloured skin, hair and eyes co-evolved as humans moved into latitudes where shorter days and summers meant they got less sunlight. (abc.net.au)
  • difficult
  • Due to the restriction of the embryo acquisition, and the number of cephalopod chromosomes up to 60, it is difficult to obtain an ideal metaphase. (pensoft.net)
  • early
  • In this chapter, we summarise current knowledge of errors in chromosome segregation during oogenesis and early embryogenesis, with special reference to the clinical implications for successful assisted reproduction. (warwick.ac.uk)
  • sequences
  • In other words, humans and chimps have DNA sequences that are greater than 98 percent similar. (pbs.org)
  • And third, whereas a normal chromosome has readily identifiable, repeating DNA sequences called telomeres at both ends, chromosome 2 also has telomere sequences not only at both ends but also in the middle. (pbs.org)
  • These results indicate that this PCR-based cDNA selection strategy yields information on a distinct subset of pancreatic islet transcribed sequences, which complements ongoing human EST identification efforts based on random cDNA selection. (diabetesjournals.org)
  • pair
  • To corroborate Darwin's theory, scientists would need to find a valid explanation for why a chromosome pair is missing in humans that is present in apes. (pbs.org)
  • One chromosome of each pair has replicated during cell division to form an identical copy, or chromatid. (sciencephoto.com)
  • cell
  • Reverse transcription-polymerase chain reaction (RTPCR) and/or Northern analysis of RNA from multiple tissues confirmed that expression was enhanced in human islet cell RNA for 11 of 15 tested cDNAs. (diabetesjournals.org)
  • disease
  • Humans have been using antibody therapies to treat infectious disease for more than 100 years. (sciencemag.org)
  • The work is preliminary and needs to be tested in people, but the team calls it a "proof-of-concept" that human antibodies can be grown in animals and retain their activity against disease. (sciencemag.org)
  • HACs have been used to create transgenic animals for use as animal models of human disease and for production of therapeutic products. (wikipedia.org)
  • include
  • Based on fossil evidence and comparative anatomy, Charles Darwin proposed that humans and great apes-which include chimpanzees, gorillas, and orangutans-share a common ancestor that lived several million years ago. (pbs.org)
  • Project
  • Nonhuman antibodies from, for instance, birds and primates, have been safely administered to people in the past, so human antibodies are expected to prove safe in phase 1 clinical trials, says reproductive physiologist Eddie Sullivan of SAB Biotherapeutics, who headed the project to develop the transchromosomal cows. (sciencemag.org)
  • high
  • Within a month, the animals were producing liters of high-concentration human antibodies against both strains. (sciencemag.org)
  • unique
  • It turns out that chromosome 2, which is unique to the human lineage of evolution, emerged as a result of the head-to-head fusion of two ancestral chromosomes that remain separate in other primates. (pbs.org)
  • mouse
  • Real benefits of virtual therapy, monkey malaria in humans, round electrons disappoint, mouse pups with two dads, bats' hover techniques, Europa's icy spikes, a vampire burial and more. (sciencenews.org)
  • conditions
  • Noninvasive fetal aneuploidy detection technology allows for the detection of fetal genetic conditions, specifically having three chromosomes, a condition called aneuploidy, by analyzing a simple blood sample from the pregnant woman. (asu.edu)
  • Animals
  • Trypanosomatids show several different classes of cellular organisation of which The parasite is the cause brucei at different stages of vertebrate animals, including humans, carried by genera of tsetse fly in sub-Saharan Africa. (floorcaresterlingheights.info)