Twin Research and Human Genetics最新文献

This population-based cohort study investigated the prevalence, potential risk factors, and consequences of birth weight discordance (BWD) among same-sex twins. We retrieved data from the automated system of healthcare utilization databases of Lombardy Region, Northern Italy (2007-2021). BWD was defined as 30% or more disparity in birth weights between the larger and the smaller twin. Multivariate logistic regression was used to analyze the risk factors of BWD in deliveries with same-sex twins. In addition, the distribution of several neonatal outcomes was assessed overall and according to BWD level (i.e., ≤20%, 21-29, and ≥30%). Finally, a stratified analysis by BWD was performed to assess the relationship between assisted reproductive technologies (ART) and neonatal outcomes. We identified 11,096 same-sex twin deliveries; 556 (5.0%) pairs of twins were affected by BWD. Multivariate logistic regression analysis showed that maternal age ≥35 years (OR 1.26, 95% CI [1.05,5.51]), low level of education (OR 1.34, 95% CI [1.05, 1.70]), and ART (OR 1.16, 95% CI [0.94, 1.44], almost significant due to the low power) were independent risk factors for BWD in same-sex twins. Conversely, parity (OR 0.73, 95% CI [0.60, 0.89]) was inversely related. All the adverse outcomes observed were more common among BWD pairs than non-BWD ones. Instead, a protective effect of ART was observed for most neonatal outcomes considered among BWD twins. Our results suggest that conception after ART increases the risk of developing a high disparity between the weights of the two twins. However, the presence of BWD may complicate twin pregnancies, compromising neonatal outcomes, regardless of the modality of conception.

This Position Statement provides guidelines to assist all health professionals who receive requests for carrier testing and laboratory staff conducting the tests.In this Statement, the term 'carrier testing' refers to genetic testing in an individual to determine whether they have inherited a pathogenic variant associated with an autosomal or X-linked recessive condition previously identified in a blood relative. Carrier testing recommendations: (1) Carrier testing should only be performed with the individual's knowledge and consent; (2) An individual considering (for themselves, or on behalf of another) whether to have a carrier test should be supported to make an informed decision; (3) The mode of inheritance, the individual's personal experience with the condition, and the healthcare setting in which the test is being performed should be considered when determining whether carrier testing should be offered by a genetic health professional. Regarding children and young people: Unless there is direct medical benefit in the immediate future, the default position should be to postpone carrier testing until the child or young person can be supported to make an informed decision. There may be some specific situations where it is appropriate to facilitate carrier testing in children and young people (see section in this article). In such cases, testing should only be offered with pre- and post-test genetic counseling in which genetic health professionals and parents/guardians should explore the rationale for testing and the interests of the child and the family.

Parkinson's disease (PD) is a complex disorder with a significant genetic component. Genetic variations associated with PD play a crucial role in the disease's inheritance and prognosis. Currently, 31 genes have been linked to PD in the OMIM database, and the number of genes and genetic variations identified is steadily increasing. To establish a robust correlation between phenotype and genotype, it is essential to compare research findings with existing literature. In this study, we aimed to identify genetic variants associated with PD using a targeted gene panel with next-generation sequencing (NGS) technology. Our objective was also to explore the idea of re-analyzing genetic variants of unknown significance (VUS). We screened 18 genes known to be related to PD using NGS in 43 patients who visited our outpatient clinic between 2018-2019. After 12-24 months, we re-evaluated the detected variants. We found 14 different heterozygous variants classified as pathogenic, likely pathogenic, or VUS in 14 individuals from nonconsanguineous families. We re-evaluated 15 variants and found changes in their interpretation. Targeted gene panel analysis with NGS can help identify genetic variants associated with PD with confidence. Re-analyzing certain variants at specific time intervals can be especially beneficial in selected situations. Our study aims to expand the clinical and genetic understanding of PD and emphasizes the importance of re-analysis.

Parents' alcohol use is associated with alcohol use of their adolescent offspring, but does this association extend to the adulthood of the offspring? We examined associations of paternal and maternal problem drinking with lifetime problem drinking of their adult offspring prospectively assessed in a population-based Finnish twin-family cohort (FinnTwin16). Problem drinking (Malmö-modified Michigan Alcoholism Screening Test) was self-reported separately by mothers and fathers when their children were 16. The children reported on an extended lifetime version of the same measure during their mid-twenties (21-28 years) and mid-thirties (31-37 years). 1235 sons and 1461 daughters in mid-twenties and 991 sons and 1278 daughters in mid-thirties had complete data. Correlations between fathers' and their adult children's problem drinking ranged from .12 to .18. For mothers and their adult children, these correlations ranged from .09 to .14. In multivariate models, adjustment for potential confounders had little effect on the observed associations. In this study, parental problem drinking was modestly associated with lifetime problem drinking of their adult children. This association could be detected even when the children had reached the fourth decade of life.

The expansion of genetic and genomic testing in clinical practice and research, and the growing market for direct-to-consumer genomic testing has led to increased awareness about the impact of this form of testing on insurance. Genetic or genomic information can be requested by providers of mutually rated insurance products, who may then use it when setting premiums or determining eligibility for cover under a particular product. Australian insurers are subject to relevant legislation and an industry led standard that was updated in 2019 to introduce a moratorium on the use of genetic test results in life insurance underwriting for policies

Individual differences in educational attainment (EA) and physical health, as indexed by body mass index (BMI), are correlated within individuals and across generations. The aim of our study was to assess the transmission of these traits from parents to their offspring in childhood and adolescence. We analyzed BMI and EA in 13,916 families from the Netherlands. Data were available for 27,577 parents (mean age 33) and 26,855 of their offspring at 4 and 12 years of age. We employed structural equation modeling to simultaneously estimate the phenotypic transmission of BMI and EA from parents to offspring, the spousal correlations, and the residual child BMI-EA associations after accounting for intergenerational transmission and testing for gender differences therein. We found a significant intergenerational transmission of BMI to BMI in childhood (age 4; standardized regression coefficient β = .10) and adolescence (age 12; β = .20), and of EA to academic achievement in adolescence (β = .19). Cross-trait parent-to-offspring transmission was weak. All transmission effects were independent of parent or offspring gender. We observed within-person EA-BMI correlations that were negative in parents (∼-.09), positive in children (∼.05) and negative in adolescents (∼-.06). Residual EA-BMI were positive in children (∼.05) and insignificant in adolescents. Spousal correlations were .46 for EA, .21 for BMI, and ∼-.09 cross-trait. After accounting for spousal correlations, the intergenerational transmission for BMI and EA is mainly predictive within, but not across, traits. The within-person correlation between BMI and EA can change in direction between childhood and adulthood.

Illicit substance use is dangerous in both acute and chronic forms, frequently resulting in lethal poisoning, addiction, and other negative consequences. Similar to research in other psychiatric conditions, whose ultimate goal is to enable effective prevention and treatment, studies in substance use are focused on factors elevating the risk for the disorder. The rapid growth of the substance use problem despite the effort invested in fighting it, however, suggests the need in changing the research approach. Instead of attempting to identify risk factors, whose neutralization is often infeasible if not impossible, it may be more promising to systematically reverse the perspective to the factors enhancing the aspect of liability to disorder that shares the same dimension but is opposite to risk, that is, resistance to substance use. Resistance factors, which enable the majority of the population to remain unaffected despite the ubiquity of psychoactive substances, may be more amenable to translation. While the resistance aspect of liability is symmetric to risk, the resistance approach requires substantial changes in sampling (high-resistance rather than high-risk) and using quantitative indices of liability. This article provides an overview and a practical approach to research in resistance to substance use/addiction, currently implemented in a NIH-funded project. The project benefits from unique opportunities afforded by the data originating from two longitudinal twin studies, the Virginia Twin Study of Adolescent and Behavioral Development and the Minnesota Twin Family Study. The methodology described is also applicable to other psychiatric disorders.

An abnormal alanine aminotransferase (ALT) level is predictive of disease and all-cause mortality and may indicate liver injury. Using twin modeling, the genetic and environmental factors that affect human serum ALT levels have been well studied for the populations in the different countries, and the results showed moderate-to-high heritability. However, the heritability of ALT level has not been explored in Chinese population. Thus, we recruited 369 pairs of twins (233 monozygotic and 136 dizygotic) from the Qingdao Twin Registry in China with a median age of 50 years (40-80 years). Correlation analysis and a structural equation model (SEM) were conducted to evaluate the heritability of ALT level. The data for age, gender, body mass index and alcohol consumption were set as covariates. Intrapair correlation in monozygotic twins was 0.64 (95%CI [.56, .71]) and 0.42 (95% CI [.28, .55]) in dizygotic twins. The SEM analysis indicated that 65% (95% CI [57%, 71%]) of the variation in ALT levels can be explained by additive genetics and 35% (95% CI [29%, 44%]) of the variation is attributed to unique environmental factors or residuals. Shared environmental influences were not significant. In conclusion, serum ALT variations exhibited strong genetic effects. The variation could also be explained by unique environmental factors. However, shared environmental factors have a minor impact on the serum ALT level.