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Nordisk Alkohol- & Narkotikatidskrift :... Aug 2023: Heritability of alcohol use disorders (AUDs) varies widely, with reported estimates of 30-78% in twin studies. This variation might be due to methodological...
: Heritability of alcohol use disorders (AUDs) varies widely, with reported estimates of 30-78% in twin studies. This variation might be due to methodological differences (e.g., using different thresholds for AUDs, age differences between samples). : To investigate the heritability of AUDs in a nation-wide sample of male and female twins in late adolescence (18 years). : The study is based on data from 8,330 18-year-old Swedish monozygotic (MZ) and dizygotic (DZ) twins from the Child and Adolescent Twin Study (Sweden). : Univariate sex-limitation twin analyses were performed using (a) total AUDIT score, (b) different AUDIT cut-offs (AUDIT-10: potentially harmful alcohol use and most likely alcohol dependent ; AUDIT-C: potential hazardous alcohol consumption/active alcohol use disorders), and (c) a risk-group classification for alcohol dependence based on AUDIT total score. : Prevalence of potential hazardous alcohol consumption/active alcohol use was 57.1%, and for potentially harmful alcohol use prevalence was 26.5%. Prevalence was higher among females (59.0% and 31.1% respectively) than males (54.4% and 20.0% respectively). Overall, the results of the univariate model fitting indicated that there were qualitative sex differences in the genetic and environmental influences on AUDs, with generally moderate heritability estimates ranging between 0.37 and 0.50. : At odds with previous research, a harmful/hazardous drinking pattern was more common in this age group among females than a low-risk drinking pattern (where males were overrepresented). Heritability estimates were moderate throughout all measures and cut-offs, with equally high contributions from shared and non-shared environment. Sex-limitation models revealed qualitative sex differences for AUDs, suggesting that different genetic and/or environmental factors influence variation in AUDs in males and females.
PubMed: 37663054
DOI: 10.1177/14550725221090383 -
European Journal of Medical Genetics Oct 2023MTSS2-related neurodevelopmental disorder (MTSS2-related NDD) (MIM 620086) is characterized by intellectual developmental disorder with ocular anomalies and distinctive...
MTSS2-related neurodevelopmental disorder (MTSS2-related NDD) (MIM 620086) is characterized by intellectual developmental disorder with ocular anomalies and distinctive facial features (IDDOF). The only existing report to date described five individuals who exhibited an identical de novo c.2011C>T (p.Arg671Trp) variant in the MTSS2 gene. Herein, we report a new case of MTSS2-related NND in a male dizygotic twin who presented with IDDOF and severe intellectual disability. This patient also displayed additional clinical features, including low functioning autism, hypothyroidism, duodenal obstruction secondary to Ladd's bands, inguinal hernias, cryptorchidism, transient subperiosteal new bone formation, and short stature with delayed bone age, which had not been previously reported in association with the MTSS2-related NDD. Exome sequencing identified the recurrent c.2011C>T (p.Arg671Trp) variant in the MTSS2 gene. The mother and the other twin tested negative for the pathogenic variant, while the father's participation in the study was unavailable. This case confirms that the MTSS2-related NDD is caused by the recurrent MTSS2 missense variant p.Arg671Trp. The novel findings identified in our patient expand the phenotypic spectrum associated with this new autosomal dominant entity, but further studies on its genetic and clinical manifestations are still needed.
Topics: Humans; Male; Autistic Disorder; Intellectual Disability; Mutation, Missense; Neurodevelopmental Disorders; Phenotype
PubMed: 37657631
DOI: 10.1016/j.ejmg.2023.104826 -
Medicina (Kaunas, Lithuania) Jul 2023: VACTERL association is a widely known congenital malformation that includes vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies. Patients with...
: VACTERL association is a widely known congenital malformation that includes vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies. Patients with VACTERL and hydrocephalus appear to form a distinct group, both genetically and phenotypically, and their condition has been called VACTERL-H syndrome. Most cases of VACTERL-H have been reported postnatally, as VACTER-H syndrome is difficult to diagnose prenatally. Here, we report a case of VACTERL-H syndrome in a dichorionic and diamniotic twin diagnosed prenatally by ultrasonography and confirmed postnatally by three-dimensional computed tomography (3D CT). A 34-year-old multiparous female was referred to our institution at 31 + 3 weeks gestation for suspected fetal ventriculomegaly. Detailed examinations using two-dimensional and Doppler ultrasounds revealed hydrocephalus, bilateral dysplastic upper arms, radial aplasia, unilateral pulmonary agenesis, dextrocardia with right atrial enlargement, a unilateral hypoplastic ectopic kidney, a single umbilical artery, a tracheoesophageal fistula with a small stomach, polyhydramnios, and anal atresia. Findings from the postnatal 3D CT aligned with the prenatal diagnosis, showing upper-limb agenesis, dextrocardia with pulmonary hypoplasia, tracheoesophageal fistula, imperforate anus, and colon dilatation. The affected 1390-g male twin had an unaffected 1890-g female twin sister and a healthy 6-year-old brother. : Upon encountering fetuses with multiple anomalies, including ventriculomegaly, a small stomach with polyhydramnios, an abnormally positioned heart, and upper-limb abnormalities, clinicians should perform systematic ultrasonographic examinations to detect associated anomalies and be aware of VACTERL-H syndrome.
Topics: Pregnancy; Humans; Female; Male; Adult; Child; Twins, Dizygotic; Tracheoesophageal Fistula; Polyhydramnios; Hydrocephalus; Ultrasonography, Prenatal; Dextrocardia
PubMed: 37629676
DOI: 10.3390/medicina59081387 -
Journal of Personality Aug 2024This study examined whether phenotypic correlations between psychopathological dimensions and personality traits of different hierarchical levels originate from common...
OBJECTIVE
This study examined whether phenotypic correlations between psychopathological dimensions and personality traits of different hierarchical levels originate from common genetic and environmental sources of variance.
METHOD
Participants were 386 monozygotic and 204 dizygotic twins. The Psychiatric Diagnostic Screening Questionnaire (PDSQ) was applied along with the Revised NEO Personality Inventory (NEO-PI-R). The results of the CFA confirmed the hypothesis of the internalizing and externalizing dimensions underlying PDSQ scales.
RESULTS
The results indicated a significantly greater role of genetic compared to environmental factors in the relationship between internalizing psychopathology and personality traits. Facets of neuroticism showed positive genetic links with internalizing disorders, while negative genetic links were shown for all facets of extraversion except excitement-seeking, competence, self-discipline, achievement striving, actions, and trust. Lower-order personality traits were shown to be associated with internalizing disorders more intensively than the broader domains to which they belong, both at the phenotypic and genetic levels.
CONCLUSIONS
High neuroticism, together with several facets from the domain of extraversion and conscientiousness seems to represent an increased genetic susceptibility to the disorders from the internalizing spectrum. Results also suggest that specific environmental factors which are not shared with personality traits contribute to the internalizing symptoms.
Topics: Humans; Male; Female; Adult; Personality; Mental Disorders; Personality Inventory; Middle Aged; Young Adult; Gene-Environment Interaction; Neuroticism; Phenotype; Twins, Monozygotic; Personality Disorders; Twins, Dizygotic; Extraversion, Psychological
PubMed: 37614221
DOI: 10.1111/jopy.12878 -
The Journal of Molecular Diagnostics :... Sep 2023Twin pregnancy constitutes significant risks for maternal and fetal health, which is usually detected by ultrasound examination at early gestation. However, the...
Twin pregnancy constitutes significant risks for maternal and fetal health, which is usually detected by ultrasound examination at early gestation. However, the imaging-based approach may not accurately identify all twins confounded by practical or clinical variables. The analysis of fetal cell-free DNA in noninvasive prenatal screening assays can completement the ultrasound method for twin detection, which differentiates fraternal or identical twins based on their distinct genotypes. Here, a new noninvasive prenatal screening employing high-coverage next-generation sequencing for targeted nucleotide polymorphisms was developed for detection of zygosity and determination of fetal fraction in twin pregnancies. This method utilizes a binary analysis of both the number and allelic fraction of fetus-specific single-nucleotide polymorphisms to infer the zygosity. In 323 samples collected from 215 singleton, 90 dizygotic, and 18 monozygotic twin pregnancies, all 90 dizygotic twins were correctly detected, with a 100% sensitivity and a 100% specificity. In addition, this method can detect complex pregnancies, such as egg donors, contamination, and twins with complete hydatidiform mole. The fetus-specific fetal fraction change was monitored in nine dizygotic twin pregnancies, which demonstrated highly variable dynamics of fetal cell-free DNA turnover up to 7 weeks after twin reduction. Overall, this study provides a new noninvasive prenatal screening strategy for the accurate identification of twin zygosity and quantification of fetal fraction, which has important clinical implications for the management of twin pregnancies.
Topics: Female; Pregnancy; Humans; Pregnancy, Twin; Polymorphism, Single Nucleotide; Fetus; Alleles; Cell-Free Nucleic Acids
PubMed: 37599029
DOI: 10.1016/j.jmoldx.2023.06.003 -
Child Development 2024According to the failure model (Patterson & Capaldi, 1990), peer rejection is the intermediary link between problem behaviors and internalizing symptoms. The present...
Reconsidering the failure model: Using a genetically controlled design to assess the spread of problems from reactive aggression to internalizing symptoms through peer rejection across the primary school years.
According to the failure model (Patterson & Capaldi, 1990), peer rejection is the intermediary link between problem behaviors and internalizing symptoms. The present study tested the model with 464 monozygotic and same-sex dizygotic twin pairs (234 female, 230 male dyads). Teacher-reported reactive aggression and internalizing symptoms, and peer-reported peer rejection were collected at ages 6, 7, and 10 (from 2001 to 2008). Support for the failure model emerged in conventional non-genetically controlled analyses, but not twin-difference score analyses (which remove shared environmental and genetic contributions). Univariate biometric models attributed minimal variance in failure model variables to shared environmental factors, suggesting that genetic factors play an important unacknowledged role in developmental pathways historically ascribed to nonshared experiences in the failure model.
Topics: Humans; Male; Female; Aggression; Peer Group; Twins; Problem Behavior; Schools; Twins, Monozygotic
PubMed: 37584073
DOI: 10.1111/cdev.13994 -
Scientific Reports Aug 2023Previous studies on brain connectivity correlates of autism have often focused on selective connections and yielded inconsistent results. By applying global fiber...
Previous studies on brain connectivity correlates of autism have often focused on selective connections and yielded inconsistent results. By applying global fiber tracking and utilizing a within-twin pair design, we aimed to contribute to a more unbiased picture of white matter connectivity in association with clinical autism and autistic traits. Eighty-seven twin pairs (n = 174; 55% monozygotic; 24 with clinical autism) underwent diffusion tensor imaging. Linear regressions assessed within-twin pair associations between structural brain connectivity of anatomically defined brain regions and both clinical autism and autistic traits. These were explicitly adjusted for IQ, other neurodevelopmental/psychiatric conditions and multiple testing, and implicitly for biological sex, age, and all genetic and environmental factors shared by twins. Both clinical autism and autistic traits were associated with reductions in structural connectivity. Twins fulfilling diagnostic criteria for clinical autism had decreased brainstem-cuneus connectivity compared to their co-twins without clinical autism. Further, twins with higher autistic traits had decreased connectivity of the left hippocampus with the left fusiform and parahippocampal areas. These associations were also significant in dizygotic twins alone. Reduced brainstem-cuneus connectivity might point towards alterations in low-level visual processing in clinical autism while higher autistic traits seemed to be more associated with reduced connectivity in networks involving the hippocampus and the fusiform gyrus, crucial especially for processing of faces and other (higher order) visual processing. The observed associations were likely influenced by both genes and environment.
Topics: Child; Humans; Autism Spectrum Disorder; Autistic Disorder; Brain; Child Development Disorders, Pervasive; Diffusion Tensor Imaging; Twins, Dizygotic; Twins, Monozygotic
PubMed: 37573391
DOI: 10.1038/s41598-023-39876-y -
Biological Psychiatry Mar 2024Attention-deficit/hyperactivity disorder (ADHD) and major depressive disorder (MDD) are two highly prevalent disorders that frequently co-occur. Prior evidence from...
BACKGROUND
Attention-deficit/hyperactivity disorder (ADHD) and major depressive disorder (MDD) are two highly prevalent disorders that frequently co-occur. Prior evidence from genetic and cohort studies supports an association between ADHD and MDD. However, the direction and mechanisms underlying their association remain unclear. As onset of ADHD occurs in early life, it has been hypothesized that ADHD may cause MDD.
METHODS
We examined the association of ADHD with MDD using 3 different genetically informed methods to disentangle causality from confounding: 1) a nationwide longitudinal register-based full sibling comparison (N = 1,018,489) adjusting for shared familial confounding; 2) a prospective co-twin control study comprising 16,477 twins (5084 monozygotic and 11,393 dizygotic); and 3) a two-sample Mendelian randomization analysis using the largest available ADHD (N = 225,534) and MDD (N = 500,199) genome-wide association study summary statistics, adjusting for correlated and uncorrelated horizontal pleiotropy.
RESULTS
Sibling and twin comparisons indicated that individuals with ADHD have an increased risk for subsequent development of MDD (hazard ratio = 4.12 [95% CI 3.62-4.69]) after adjusting for shared genetic and familial factors and that ADHD scores endorsed by parents are positively associated with subsequent MDD scores at ages 15 and 18 years (b = 0.07 [95% CI 0.05-0.08] and b = 0.09 [95% CI 0.08-0.11], respectively). Mendelian randomization analyses showed that genetic liability for ADHD is causally related to MDD (odds ratio = 1.15 [95% CI 1.08-1.23]).
CONCLUSIONS
Our study provides consistent results across 3 different genetically informative approaches, strengthening the hypothesis that ADHD is causally related to MDD.
Topics: Humans; Attention Deficit Disorder with Hyperactivity; Depressive Disorder, Major; Genome-Wide Association Study; Prospective Studies; Risk Factors; Mendelian Randomization Analysis
PubMed: 37562520
DOI: 10.1016/j.biopsych.2023.07.017 -
Journal of Personality Aug 2024The present study aimed to provide a seminal behavioral genetic analysis of time perspectives (TPs). Moreover, we intended to investigate the magnitude of genetic vs....
OBJECTIVE
The present study aimed to provide a seminal behavioral genetic analysis of time perspectives (TPs). Moreover, we intended to investigate the magnitude of genetic vs. environmental components of the well-established assocations between TPs and personality features.
BACKGROUND
Individual differences in temporal framing processes, referred to as TPs, are vital psychological and behavioral outcomes. Although proponents of TP theory emphasize mainly environmental origins of the tendencies to adopt certain TPs, research provides evidence for marked associations between the temporal dimensions and major personality traits that are known to be heritable. Hence, it was essential to empirically verify these claims.
METHOD
The article reports an analysis of genetic and environmental components of variance in TPs based on a study adopting a twin design, conducted on a sample of 393 pairs of twins (135 monozygotic and 258 dizygotic).
RESULTS
Multivariate Cholesky decomposition supported an EA model assuming impacts of both unshared environmental factors (E) and additive genetic factors (A) across all TP dimensions, suggesting that the effects of shared environment on TPs are plausibly negligible. Heritability indices of TPs ranged between 0.51 for Present-Fatalistic and 0.62 for Present-Hedonistic, suggesting that the majority of the variance in TPs stems from genetic influences. Substantial genetic correlations were found between TPs and the Big Five personality traits.
CONCLUSIONS
The findings provide further evidence for conceptualizing TPs as biologically based personality traits and challenge the claims that TP is mainly a product of culture, education, and personal experiences.
Topics: Humans; Personality; Male; Female; Adult; Twins, Monozygotic; Genetics, Behavioral; Young Adult; Twins, Dizygotic; Time Perception; Middle Aged
PubMed: 37551866
DOI: 10.1111/jopy.12870 -
SAGE Open Medical Case Reports 2023It is a rare condition in twin pregnancies for a fetus to coexist with a complete hydatidiform mole, present with complications, and result in a healthy neonate. Only a...
It is a rare condition in twin pregnancies for a fetus to coexist with a complete hydatidiform mole, present with complications, and result in a healthy neonate. Only a few cases have been reported upon review of the literature. Early diagnosis is essential because this type of pregnancy is associated with serious complications and management challenges. The complications associated with these pregnancies include antepartum hemorrhage, hyperthyroidism, preeclampsia, prematurity, fetal death, and gestational trophoblastic neoplasia. Here, we describe a case of dizygotic twin pregnancy in which a complete mole coexists with a normal fetus, complicated by hyperthyroidism, that resulted in the birth of a 1700-g female alive neonate who is euthyroid to a 25-year-old primigravida at a gestational age of 33 weeks by emergency cesarean section for an indication of a twin pregnancy molar coexisting with an alive fetus in labor. The mother had been on conservative management and treated as an inpatient for hyperthyroidism. In our country, there have been three case reports of partial moles with coexisting alive fetuses, but this is the first case report of a complete mole with a coexisting alive fetus.
PubMed: 37533490
DOI: 10.1177/2050313X231189404