Matt McGue

STUDY QUESTION Which genetic factors regulate female propensity for giving birth to spontaneous dizygotic (DZ) twins? SUMMARY ANSWER We identified four new loci, GNRH1, FSHR, ZFPM1, and IPO8, in addition to previously identified loci, FSHB and SMAD3. WHAT IS KNOWN ALREADY The propensity to give birth to DZ twins runs in families. Earlier, we reported that FSHB and SMAD3 as associated with DZ twinning and female fertility measures. STUDY DESIGN, SIZE, DURATION We conducted a genome-wide association meta-analysis (GWAMA) of mothers of spontaneous dizygotic (DZ) twins (8265 cases, 264 567 controls) and of independent DZ twin offspring (26 252 cases, 417 433 controls). PARTICIPANTS/MATERIALS, SETTING, METHODS Over 700 000 mothers of DZ twins, twin individuals …

Introduction Using cannabis as a sleep aid is common. However, little is known about how this practice relates to mental health and substance use. To address this, we examined associations between using cannabis as a sleep aid with mental health and substance use outcomes using a co-twin control design. Methods Participants were 3,165 adults (Mage=36.7 (SD=5.3)) from two population-based twin cohorts. Outcomes of interest included mental health constructs (e.g. depression, impulsivity), substance use measures (frequency and problems from use of specific substances), and use of other substances for sleep. First, we conducted regression models to test phenotypic associations between endorsing past month use of cannabis to aid sleep (yes/no) and the above outcomes. Next, we used multilevel models to examine whether significant phenotypic associations were …

Organizational citizenship behavior (OCB) is often viewed as an unequivocal boon. However, differing motivations and external pressures can change OCB’s relationship with counterproductive work behavior (CWB) and sexual harassment. We take a novel approach to understanding the relationship between OCB, CWB and sexual harassment by exploring the role of engaging in interpersonally directed OCB and CWB because of targeted colleagues’ sex or gender. We use the terms “gendered OCB” and “gendered CWB” to refer to engaging in OCB or CWB because of the gender or sex of the target of the behavior (e.g. a colleague). We examined the relationships among OCB, CWB, and sexual harassment in a sample of 503 Prolific users (60.2% men) in the United States. Interpersonally directed OCB that was sex/gender agnostic had near-zero correlations with general CWB and sexual harassment. However …

Background: The WNT signaling pathway is involved in a wide range of developmental events and maintenance of homeostasis in adult tissue, including lung development and health. WNT signaling genes have also been suggested to play a role in pathogenesis of lung diseases such as chronic obstructive pulmonary disease (COPD) and asthma.Aims and Objectives: The aim of this meta-analysis was to identify consistent disease markers for COPD, asthma, forced expiratory volume in one second (FEV1), and forced vital capacity (FVC) in nine genes of the WNT signaling cascade pathway (WNT10b, WIF1, WISP1, SFRP2, SFRP5, DKK1, Axin2, TCF7L2, and FZD3) using genome-wide association data from six European cohort studies.Methods: The six European cohort studies included are: B58C (UK), ECRHS (multicentre), EGEA (France), GINI / LISA (Germany), NFBC1966 (Finland), and SAPALDIA …

Background Cannabis use is associated with outcomes like income, legal problems, and psychopathology. This finding rests largely on correlational research designs, which rely at best on statistical controls for confounding. Here, we control for unmeasured confounders using a longitudinal study of twins. Method In a sample of 4,078 American adult twins first assessed decades ago, we used cotwin control mixed effects models to evaluate the effect of lifetime average frequency of cannabis consumption measured on substance use, psychiatric, and psychosocial outcomes. Results On average, participants had a lifetime cannabis frequency of about one to two times per month, across adolescence and adulthood. As expected, in individual-level analyses, cannabis use was significantly associated with almost all outcomes in the expected directions. However, when comparing each twin to their cotwin, which …

Aims To estimate the effect of recreational legalization on cannabis use frequency and sources of variance across legal environments. Design Longitudinal discordant twin and gene–environment interaction models in twins recruited from birth records and assessed prospectively. Setting The United States, including states with different recreational cannabis policies before and after 2014, when recreational cannabis was first legalized. Participants Two longitudinal, prospectively assessed samples of American twins aged 24–47 (n = 1425 in legal states, n = 1996 in illegal states), including 111 monozygotic pairs discordant for residence. Measurements Current cannabis use frequency (measured continuously and ordinally) was the primary outcome, and the predictor was recreational status of cannabis (legal/illegal) in the participant’s state of residence at the time of assessment. Covariates include age, sex …

Saving disposition, the tendency to save rather than consume, has been found to be associated with economic outcomes. People lacking the disposition to save are more likely to experience financial distress. This association could be driven by other economic factors, behavioral traits, or even genetic effects. Using a sample of 3,920 American twins, we develop scales to measure saving disposition and financial distress. We find genetic influences on both traits, but also a large effect of the rearing family environment on saving disposition. We estimate that 44% of the covariance between the two traits is due to genetic effects. Saving disposition remains strongly associated with lower financial distress, even after controlling for family income, cognitive ability, and personality traits. The association persists within families and monozygotic twin pairs; the twin who saves more tends to be the twin who experiences less …

Background: As more states pass recreational cannabis legalization (RCL), we must understand how RCL affects substance use.Objectives: The current study aims to examine the effect of RCL on lifetime and past-year use of cannabis, alcohol, tobacco, and other drugs, frequency of cannabis, alcohol, and tobacco use, co-use of cannabis with alcohol and tobacco, and consequences from cannabis and alcohol use.Methods: We used a unique, co-twin control design of twin pairs who were discordant for living in a state with RCL between 2018 and 2021. The sample consisted of 3,830 adult twins (41% male), including 232 twin pairs discordant for RCL. Problems from alcohol and cannabis use were assessed via the Brief Marijuana Consequences Questionnaire and the Brief Young Adult Alcohol Consequences Questionnaire.Results: Results indicated that the twin living in an RCL state was more likely to endorse …