Twin Studies as Topic: Methods of detecting genetic etiology in human traits. The basic premise of twin studies is that monozygotic twins, being formed by the division of a single fertilized ovum, carry identical genes, while dizygotic twins, being formed by the fertilization of two ova by two different spermatozoa, are genetically no more similar than two siblings born after separate pregnancies. (Last, J.M., A Dictionary of Epidemiology, 2d ed)Twins: Two individuals derived from two FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother. Twins are either monozygotic (TWINS, MONOZYGOTIC) or dizygotic (TWINS, DIZYGOTIC).Diseases in Twins: Disorders affecting TWINS, one or both, at any age.Twins, Monozygotic: Two off-spring from the same PREGNANCY. They are from a single fertilized OVUM that split into two EMBRYOS. Such twins are usually genetically identical and of the same sex.Twins, ConjoinedTwins, Dizygotic: Two offspring from the same PREGNANCY. They are from two OVA, fertilized at about the same time by two SPERMATOZOA. Such twins are genetically distinct and can be of different sexes.Twin StudyEnvironment: The external elements and conditions which surround, influence, and affect the life and development of an organism or population.Pregnancy, Twin: The condition of carrying TWINS simultaneously.Social Environment: The aggregate of social and cultural institutions, forms, patterns, and processes that influence the life of an individual or community.Genetics, Behavioral: The experimental study of the relationship between the genotype of an organism and its behavior. The scope includes the effects of genes on simple sensory processes to complex organization of the nervous system.VirginiaVietnam Conflict: A conflict occurring from 1954 through 1975 within the Republic of Vietnam. It involved neighboring nations and the United States and other members of the Southeast Asia Treaty Organization.Genetic Predisposition to Disease: A latent susceptibility to disease at the genetic level, which may be activated under certain conditions.Inheritance Patterns: The different ways GENES and their ALLELES interact during the transmission of genetic traits that effect the outcome of GENE EXPRESSION.Phenotype: The outward appearance of the individual. It is the product of interactions between genes, and between the GENOTYPE and the environment.Registries: The systems and processes involved in the establishment, support, management, and operation of registers, e.g., disease registers.Conduct Disorder: A repetitive and persistent pattern of behavior in which the basic rights of others or major age-appropriate societal norms or rules are violated. These behaviors include aggressive conduct that causes or threatens physical harm to other people or animals, nonaggressive conduct that causes property loss or damage, deceitfulness or theft, and serious violations of rules. The onset is before age 18. (From DSM-IV, 1994)Models, Genetic: Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.Triplets: Three individuals derived from three FETUSES that were fertilized at or about the same time, developed in the UTERUS simultaneously, and born to the same mother.Pregnancy, Multiple: The condition of carrying two or more FETUSES simultaneously.Longitudinal Studies: Studies in which variables relating to an individual or group of individuals are assessed over a period of time.SwedenQuantitative Trait, Heritable: A characteristic showing quantitative inheritance such as SKIN PIGMENTATION in humans. (From A Dictionary of Genetics, 4th ed)Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Aptitude: The ability to acquire general or special types of knowledge or skill.Individuality: Those psychological characteristics which differentiate individuals from one another.Fetofetal Transfusion: Passage of blood from one fetus to another via an arteriovenous communication or other shunt, in a monozygotic twin pregnancy. It results in anemia in one twin and polycythemia in the other. (Lee et al., Wintrobe's Clinical Hematology, 9th ed, p737-8)Genotype: The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.Biometry: The use of statistical and mathematical methods to analyze biological observations and phenomena.Heredity: The transmission of traits encoded in GENES from parent to offspring.Genetic Variation: Genotypic differences observed among individuals in a population.Antisocial Personality Disorder: A personality disorder whose essential feature is a pervasive pattern of disregard for, and violation of, the rights of others that begins in childhood or early adolescence and continues into adulthood. The individual must be at least age 18 and must have a history of some symptoms of CONDUCT DISORDER before age 15. (From DSM-IV, 1994)Attention Deficit Disorder with Hyperactivity: A behavior disorder originating in childhood in which the essential features are signs of developmentally inappropriate inattention, impulsivity, and hyperactivity. Although most individuals have symptoms of both inattention and hyperactivity-impulsivity, one or the other pattern may be predominant. The disorder is more frequent in males than females. Onset is in childhood. Symptoms often attenuate during late adolescence although a minority experience the full complement of symptoms into mid-adulthood. (From DSM-V)Questionnaires: Predetermined sets of questions used to collect data - clinical data, social status, occupational group, etc. The term is often applied to a self-completed survey instrument.Marijuana Abuse: The excessive use of marijuana with associated psychological symptoms and impairment in social or occupational functioning.Genetic Linkage: The co-inheritance of two or more non-allelic GENES due to their being located more or less closely on the same CHROMOSOME.Temperament: Predisposition to react to one's environment in a certain way; usually refers to mood changes.Sex Factors: Maleness or femaleness as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or effect of a circumstance. It is used with human or animal concepts but should be differentiated from SEX CHARACTERISTICS, anatomical or physiological manifestations of sex, and from SEX DISTRIBUTION, the number of males and females in given circumstances.Dyslexia: A cognitive disorder characterized by an impaired ability to comprehend written and printed words or phrases despite intact vision. This condition may be developmental or acquired. Developmental dyslexia is marked by reading achievement that falls substantially below that expected given the individual's chronological age, measured intelligence, and age-appropriate education. The disturbance in reading significantly interferes with academic achievement or with activities of daily living that require reading skills. (From DSM-IV)Siblings: Persons or animals having at least one parent in common. (American College Dictionary, 3d ed)Australia: The smallest continent and an independent country, comprising six states and two territories. Its capital is Canberra.Pregnancy: The status during which female mammals carry their developing young (EMBRYOS or FETUSES) in utero before birth, beginning from FERTILIZATION to BIRTH.Bulimia Nervosa: An eating disorder that is characterized by a cycle of binge eating (BULIMIA or bingeing) followed by inappropriate acts (purging) to avert weight gain. Purging methods often include self-induced VOMITING, use of LAXATIVES or DIURETICS, excessive exercise, and FASTING.Birth Weight: The mass or quantity of heaviness of an individual at BIRTH. It is expressed by units of pounds or kilograms.Genome-Wide Association Study: An analysis comparing the allele frequencies of all available (or a whole GENOME representative set of) polymorphic markers in unrelated patients with a specific symptom or disease condition, and those of healthy controls to identify markers associated with a specific disease or condition.Diagnostic and Statistical Manual of Mental Disorders: Categorical classification of MENTAL DISORDERS based on criteria sets with defining features. It is produced by the American Psychiatric Association. (DSM-IV, page xxii)Myopia: A refractive error in which rays of light entering the EYE parallel to the optic axis are brought to a focus in front of the RETINA when accommodation (ACCOMMODATION, OCULAR) is relaxed. This results from an overly curved CORNEA or from the eyeball being too long from front to back. It is also called nearsightedness.Cohort Studies: Studies in which subsets of a defined population are identified. These groups may or may not be exposed to factors hypothesized to influence the probability of the occurrence of a particular disease or other outcome. Cohorts are defined populations which, as a whole, are followed in an attempt to determine distinguishing subgroup characteristics.Personality Assessment: The determination and evaluation of personality attributes by interviews, observations, tests, or scales. Articles concerning personality measurement are considered to be within scope of this term.Adolescent Development: The continuous sequential physiological and psychological changes during ADOLESCENCE, approximately between the age of 13 and 18.DenmarkVeterans: Former members of the armed services.FinlandAlcoholism: A primary, chronic disease with genetic, psychosocial, and environmental factors influencing its development and manifestations. The disease is often progressive and fatal. It is characterized by impaired control over drinking, preoccupation with the drug alcohol, use of alcohol despite adverse consequences, and distortions in thinking, most notably denial. Each of these symptoms may be continuous or periodic. (Morse & Flavin for the Joint Commission of the National Council on Alcoholism and Drug Dependence and the American Society of Addiction Medicine to Study the Definition and Criteria for the Diagnosis of Alcoholism: in JAMA 1992;268:1012-4)Infant, Newborn: An infant during the first month after birth.Polymorphism, Single Nucleotide: A single nucleotide variation in a genetic sequence that occurs at appreciable frequency in the population.Models, Statistical: Statistical formulations or analyses which, when applied to data and found to fit the data, are then used to verify the assumptions and parameters used in the analysis. Examples of statistical models are the linear model, binomial model, polynomial model, two-parameter model, etc.Aging: The gradual irreversible changes in structure and function of an organism that occur as a result of the passage of time.Depressive Disorder, Major: Marked depression appearing in the involution period and characterized by hallucinations, delusions, paranoia, and agitation.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.Family Health: The health status of the family as a unit including the impact of the health of one member of the family on the family as a unit and on individual family members; also, the impact of family organization or disorganization on the health status of its members.Personality: Behavior-response patterns that characterize the individual.Puberty: A period in the human life in which the development of the hypothalamic-pituitary-gonadal system takes place and reaches full maturity. The onset of synchronized endocrine events in puberty lead to the capacity for reproduction (FERTILITY), development of secondary SEX CHARACTERISTICS, and other changes seen in ADOLESCENT DEVELOPMENT.Age Factors: Age as a constituent element or influence contributing to the production of a result. It may be applicable to the cause or the effect of a circumstance. It is used with human or animal concepts but should be differentiated from AGING, a physiological process, and TIME FACTORS which refers only to the passage of time.Tobacco Use Disorder: Tobacco used to the detriment of a person's health or social functioning. Tobacco dependence is included.Eating Disorders: A group of disorders characterized by physiological and psychological disturbances in appetite or food intake.Regression Analysis: Procedures for finding the mathematical function which best describes the relationship between a dependent variable and one or more independent variables. In linear regression (see LINEAR MODELS) the relationship is constrained to be a straight line and LEAST-SQUARES ANALYSIS is used to determine the best fit. In logistic regression (see LOGISTIC MODELS) the dependent variable is qualitative rather than continuously variable and LIKELIHOOD FUNCTIONS are used to find the best relationship. In multiple regression, the dependent variable is considered to depend on more than a single independent variable.Borderline Personality Disorder: A personality disorder marked by a pattern of instability of interpersonal relationships, self-image, and affects, and marked impulsivity beginning by early adulthood and present in a variety of contexts. (DSM-IV)Cognition: Intellectual or mental process whereby an organism obtains knowledge.Pregnancy Reduction, Multifetal: Selective abortion of one or more embryos or fetuses in a multiple gestation pregnancy. The usual goal is to improve the outcome for the remaining embryos or fetuses.Multivariate Analysis: A set of techniques used when variation in several variables has to be studied simultaneously. In statistics, multivariate analysis is interpreted as any analytic method that allows simultaneous study of two or more dependent variables.Genetic Markers: A phenotypically recognizable genetic trait which can be used to identify a genetic locus, a linkage group, or a recombination event.Child Development Disorders, Pervasive: Severe distortions in the development of many basic psychological functions that are not normal for any stage in development. These distortions are manifested in sustained social impairment, speech abnormalities, and peculiar motor movements.Family: A social group consisting of parents or parent substitutes and children.Body Mass Index: An indicator of body density as determined by the relationship of BODY WEIGHT to BODY HEIGHT. BMI=weight (kg)/height squared (m2). BMI correlates with body fat (ADIPOSE TISSUE). Their relationship varies with age and gender. For adults, BMI falls into these categories: below 18.5 (underweight); 18.5-24.9 (normal); 25.0-29.9 (overweight); 30.0 and above (obese). (National Center for Health Statistics, Centers for Disease Control and Prevention)ReadingGestational Age: The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated as the time from the last day of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization.Age of Onset: The age, developmental stage, or period of life at which a disease or the initial symptoms or manifestations of a disease appear in an individual.Pedigree: The record of descent or ancestry, particularly of a particular condition or trait, indicating individual family members, their relationships, and their status with respect to the trait or condition.Substance-Related Disorders: Disorders related to substance abuse.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Models, Psychological: Theoretical representations that simulate psychological processes and/or social processes. These include the use of mathematical equations, computers, and other electronic equipment.Anxiety Disorders: Persistent and disabling ANXIETY.Interview, Psychological: A directed conversation aimed at eliciting information for psychiatric diagnosis, evaluation, treatment planning, etc. The interview may be conducted by a social worker or psychologist.Alcohol Drinking: Behaviors associated with the ingesting of alcoholic beverages, including social drinking.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Fetal Death: Death of the developing young in utero. BIRTH of a dead FETUS is STILLBIRTH.Autistic Disorder: A disorder beginning in childhood. It is marked by the presence of markedly abnormal or impaired development in social interaction and communication and a markedly restricted repertoire of activity and interest. Manifestations of the disorder vary greatly depending on the developmental level and chronological age of the individual. (DSM-V)Comorbidity: The presence of co-existing or additional diseases with reference to an initial diagnosis or with reference to the index condition that is the subject of study. Comorbidity may affect the ability of affected individuals to function and also their survival; it may be used as a prognostic indicator for length of hospital stay, cost factors, and outcome or survival.Chorion: The outermost extra-embryonic membrane surrounding the developing embryo. In REPTILES and BIRDS, it adheres to the shell and allows exchange of gases between the egg and its environment. In MAMMALS, the chorion evolves into the fetal contribution of the PLACENTA.Pregnancy Outcome: Results of conception and ensuing pregnancy, including LIVE BIRTH; STILLBIRTH; SPONTANEOUS ABORTION; INDUCED ABORTION. The outcome may follow natural or artificial insemination or any of the various ASSISTED REPRODUCTIVE TECHNIQUES, such as EMBRYO TRANSFER or FERTILIZATION IN VITRO.Child Behavior: Any observable response or action of a child from 24 months through 12 years of age. For neonates or children younger than 24 months, INFANT BEHAVIOR is available.Life Change Events: Those occurrences, including social, psychological, and environmental, which require an adjustment or effect a change in an individual's pattern of living.Psychiatric Status Rating Scales: Standardized procedures utilizing rating scales or interview schedules carried out by health personnel for evaluating the degree of mental illness.Genetic Association Studies: The analysis of a sequence such as a region of a chromosome, a haplotype, a gene, or an allele for its involvement in controlling the phenotype of a specific trait, metabolic pathway, or disease.Likelihood Functions: Functions constructed from a statistical model and a set of observed data which give the probability of that data for various values of the unknown model parameters. Those parameter values that maximize the probability are the maximum likelihood estimates of the parameters.Parents: Persons functioning as natural, adoptive, or substitute parents. The heading includes the concept of parenthood as well as preparation for becoming a parent.Ultrasonography, Prenatal: The visualization of tissues during pregnancy through recording of the echoes of ultrasonic waves directed into the body. The procedure may be applied with reference to the mother or the fetus and with reference to organs or the detection of maternal or fetal disease.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Adolescent Behavior: Any observable response or action of an adolescent.Smoking: Inhaling and exhaling the smoke of burning TOBACCO.Neuropsychological Tests: Tests designed to assess neurological function associated with certain behaviors. They are used in diagnosing brain dysfunction or damage and central nervous system disorders or injury.Educational Status: Educational attainment or level of education of individuals.Gene-Environment Interaction: The combined effects of genotypes and environmental factors together on phenotypic characteristics.Depressive Disorder: An affective disorder manifested by either a dysphoric mood or loss of interest or pleasure in usual activities. The mood disturbance is prominent and relatively persistent.Great BritainPolymorphism, Genetic: The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.Sex Characteristics: Those characteristics that distinguish one SEX from the other. The primary sex characteristics are the OVARIES and TESTES and their related hormones. Secondary sex characteristics are those which are masculine or feminine but not directly related to reproduction.Statistics as Topic: The science and art of collecting, summarizing, and analyzing data that are subject to random variation. The term is also applied to the data themselves and to the summarization of the data.Norway
  • Home / Test Division / Reference Database / 2000 to 2009 / 2001 / Does spinal cord injury affect personality? (umn.edu)
  • ABSTRACT: The genetic profile of Palestinians has, for the first time, been studied by using human leukocyte antigen (HLA) gene variability and haplotypes. (yahoo.com)
  • Alcohol consumption, binge drinking, and early coronary calcification: findings from the Coronary Artery Risk Development in Young Adults (CARDIA) Study. (medscape.com)
  • These findings are important because decreased HRV is a heart disease risk factor," says Emory Heart Center cardiologist Viola Vaccarino MD, Ph.D., lead author of the study. (innovations-report.com)
  • findings in twins can be extended toward the general singleton population. (jneurosci.org)
  • Different findings have been reported for neonatal and maternal outcomes, and these variations may be a result of differences in the studied populations and/or in the management of twin pregnancy. (who.int)
  • Given these varying findings, we aimed to compare maternal, perinatal and obstetric outcomes in dichorionic twin pregnancies conceived spontaneously and through assisted reproductive technology in Erbil city, Kurdistan region, Iraq. (who.int)
  • Conclusions These findings suggest that prenatal programming of adult blood pressure occurs at least in female twins. (ahajournals.org)
  • These findings are consistent with the results of molecular genetic studies that have suggested differential modes of intergenerational transmission for SA and MA. (pubmedcentralcanada.ca)
  • Studies that have looked at ethnic differences in BED have not found any significant findings. (eatingdisorderhope.com)
  • With the recent rapid development in modern biotechnology of high-throughput genetic and genomic analyses, twin modelling is expanding from analysis of diseases to molecular phenotypes in functional genomics especially in epigenetics, a thriving field of research that concerns the environmental regulation of gene expression through DNA methylation, histone modification, microRNA and long non-coding RNA expression, etc. (biologists.org)
  • Epigenome-wide analyses in adult female twins identified specific DNA methylation changes linked to self-reported periodontal disease. (springer.com)
  • Relying on these " umbrella diagnoses ", genetic analyses, including genome-wide association studies (GWAS), were undertaken but failed to provide insight into the biological basis of these disorders. (mdpi.com)
  • 74 individuals with complete laboratory data were further studied for association analyses. (hindawi.com)
  • The balance of questions was between retaining items from earlier questionnaires to permit longitudinal analyses and including items of relevance to these twins now in their mid-thirties. (helsinki.fi)
  • Participants were identified from birth records of all twins born in England and Wales between 1994 and 1996. (wikipedia.org)
  • In hypertension, 2 independent case-control studies (1266 subjects with 53% women and 927 subjects with 24% women) replicated the effect of C-824T in the determination of blood pressure. (ahajournals.org)
  • The reason for this is that unlike cross-sectional studies , in which different individuals with the same characteristics are compared, longitudinal studies track the same people and so the differences observed in those people are less likely to be the result of cultural differences across generations. (wikipedia.org)
  • However, because of the repeated observation at the individual level, they have more power than cross-sectional observational studies, by virtue of being able to exclude time-invariant unobserved individual differences and also of observing the temporal order of events. (wikipedia.org)
  • In studies of twins, 70%-80% of differences in BMD (measured at the lumbar spine and femoral neck) between individuals is attributable to genetic factors. (mja.com.au)
  • Studies are needed to assess the reasons for the differences in perinatal and maternal outcomes between twin pregnancies conceived spontaneously and through assisted reproductive technology. (who.int)
  • DeFries JC and Fulker DW (1988) Multiple regression analysis of twin data: etiology of deviant scores versus individual differences. (els.net)
  • We have previously shown differences in angiogenic and placental growth factors in maternal blood in pregnancies complicated by TTTS compared to twin pregnancies not complicated by TTTS but matched for gestation. (biomedcentral.com)
  • This fMRI study aimed to examine how differences in literacy processing demands may affect cortical activation patterns in 11- to 12-year-old children with dyslexia as compared to children with typical reading skills. (frontiersin.org)
  • Rather than compare sets of twins where only one female experienced CSA, researchers group all twins together, and then statistically controlled for differences between twin pairs. (basisonline.org)
  • Family studies, 7- 9 ethnic differences, 10 and twin studies 11- 13 have underlined the contribution of an important genetic susceptibility in the pathogenesis of IBD. (bmj.com)
  • 5 studied environmental effects and found that differences in life choices before the age of 25 years have a sustained effect. (mivision.com.au)
  • No evidence was found of differential transmission through mothers or fathers, although the study had limited power to detect such differences. (bmj.com)
  • They partitioned co-variation amongst relatives into genetic and environmental elements, anticipating the later work of Fisher and Wright, including the effect of dominance on similarity of relatives, and beginning the first classic-twin studies. (wikipedia.org)
  • Genetic and environmental influences on sexual orientation and its correlates in an Australian twin sample. (springer.com)
  • Structural equation modelling is a standard tool in twin research and involves solving a series of simultaneous linear structural equations to estimate genetic and environmental parameters that best fit the observed twin variances and covariances. (els.net)
  • In the present study, we applied the twin approach to estimate the contribution of genetic and environmental causes that may underlie the birth weight-adult blood pressure association. (ahajournals.org)
  • His study compared twin pairs age 9-10 and 13-14 to normal siblings born within a few years of one another. (wikipedia.org)
  • The power of twin designs arises from the fact that twins may be either monozygotic (identical (MZ): developing from a single fertilized egg and therefore sharing all of their alleles) - or dizygotic (DZ: developing from two fertilized eggs and therefore sharing on average 50% of their polymorphic alleles, the same level of genetic similarity as found in non-twin siblings). (wikipedia.org)
  • In research announced today at the American College of Cardiology s 53rd Scientific Sessions in New Orleans, the scientists say they found a decrease in heart rate variability (HRV) in those twins who were depressed as compared to their non-depressed siblings. (innovations-report.com)
  • Siblings, multiple births, and the incidence of allergic disease: a birth cohort study using the West Midlands general practice research database. (springer.com)
  • Recent studies of idiopathic autism spectrum disorders (ASD) have implicated disparate genetic pathways for families in which ASD affects only one individual in the family ("simplex" autism, SA) versus multiple siblings in the family (familial or "multiplex" autism, MA). (pubmedcentralcanada.ca)
  • From these studies, a recurrence risk for siblings (lambda s (λ s )) of 15 has been calculated for IBD overall (25 for CD and 10 for UC). (bmj.com)
  • The condition recurs more than expected among twins, 9 10 11 as well as among siblings in general, 12 13 14 15 and an excess risk of cerebral palsy in children with a parent or other family member affected by the condition has been reported. (bmj.com)
  • 5,6 As in most singleton studies, only resting BP was measured, although 24-hour ambulatory registration is considered more representative of a subject's usual or true BP. (ahajournals.org)
  • DNA methylation profiles were generated using the Infinium HumanMethylation450 BeadChip in whole blood, buccal, and adipose tissue samples from predominantly older female twins (mean age 58) from the TwinsUK cohort. (springer.com)
  • The diagnostic validity of melancholic major depression in a population-based sample of female twins. (nih.gov)
  • We report two cases of primary Raynaud's phenomenon in 16 year old monozygotic female twins. (bmj.com)
  • The female twins were born at 38 weeks of gestation by caesarean section. (bmj.com)
  • This study found evidence of familial clustering in LCPD but did not show a genetic component. (aappublications.org)
  • In a well-conducted twin study of 542 families, a single underlying trait for conduct disorder, antisocial personality, alcohol dependence, and drug dependence was found, which was highly heritable and was observed in both sexes. (medscape.com)
  • 17 - 19 Various studies have found significant inherited components of fracture risk (eg, 25% of liability for Colles' fracture, a twofold hip fracture risk with a maternal hip fracture, a threefold risk of hip and other fractures with a paternal wrist fracture). (mja.com.au)
  • betes and, if so, whether obesity mediated this relationship in a Similarly, a 30-year prospective study found significant associ- population-representative sample of young adults. (cdc.gov)
  • James Pennebaker (2000) found that students who were assigned the task of writing about traumas they had suffered and about their fears, relationships and desires had stronger immune systems and were healthier than students who were assigned to write about less emotionally charged topics. (ablechild.org)
  • Researchers have found that many widely accepted dietary guidelines are not suitable for everyone, with even twins responding differently to the same foods. (news-medical.net)
  • A study funded by the USA National Institute of Drug Abuse found that "Among more than 1,400 adult females, childhood sexual abuse was associated with increased likelihood of drug dependence, alcohol dependence, and psychiatric disorders. (thefullwiki.org)
  • Finally, the associations found to be significant were tested in a twin-control study design. (biomedcentral.com)
  • Previous studies have found increased brain weight, head circumference, and MRI brain volume in children with autism. (neurology.org)
  • 26,27 ⇓ However, not all studies have found evidence of increased brain size 28,29 ⇓ or weight. (neurology.org)
  • 31 A recent study 6 found that brain volumes on MRI scans of very young children with autism (2 to 4 years) were abnormally large, whereas brain volumes at older ages (5 to 16 years) tended to be smaller than normal. (neurology.org)
  • First-born rather than second-born twins have been reported to be at higher risk, but no association between birth order and CD risk was found in other studies. (uspharmacist.com)
  • An increased risk was found among the twins of affected persons for stomach, colorectal, lung, breast, and prostate cancer. (nih.gov)
  • 2, 7, 8 MacGregor et al first assessed the genetic basis of RP in a population based twin study and found a substantial genetic contribution to the symptoms of RP. (bmj.com)
  • However, studies of brain size in adults with autism have yielded conflicting results. (neurology.org)
  • In addition, several studies have reported an increase in the overall size and weight of the brain in individuals with autism. (neurology.org)
  • The current study assessed brain volume and head circumference in a large sample of non-mentally retarded individuals with autism between 8 and 46 years of age and examined the association between age and these measurements. (neurology.org)
  • Fourteen of the autism-control pairs were included in our previous study of amygdala and hippocampal volume. (neurology.org)
  • 7 Subjects with autism represented all consecutive referrals to a research clinic that met inclusion and exclusion criteria for the study. (neurology.org)
  • Characterization of QAT and other endophenotypes among close relatives may be useful for reducing sample heterogeneity in future genetic and neurobiologic studies of autism. (pubmedcentralcanada.ca)
  • Genetic predisposition to autism has been demonstrated in families and twin studies. (hindawi.com)
  • Several studies reported on the role of X-linked creatine transporter mutations in individuals with mental retardation, with or without autism. (hindawi.com)
  • Genetic factors for autism have been well established in family and twin studies. (hindawi.com)
  • Finally, a record linkage study in Sweden, using a multisource approach of all trajectories to a diagnosis of an autism spectrum disorder in Stockholm county, reported that 2.5% of all teenagers had received a clinical diagnosis of autism spectrum disorder. (bmj.com)
  • Doll R, Peto R, Boreham J, Sutherland I. Mortality in relation to alcohol consumption: a prospective study among male British doctors. (medscape.com)
  • Epigenome-wide association scans (EWAS) of gingival bleeding and tooth mobility were conducted in whole blood in 528 and 492 twins, respectively. (springer.com)