The Quebec Newborn Twin Study at 21

Abstract

This paper is a revised and updated edition of a previous description of the Quebec Newborn Twin Study (QNTS), an ongoing prospective longitudinal follow-up of a birth cohort of twins born between 1995 and 1998 in the greater Montreal area, Québec, Canada. The goal of QNTS is to document individual differences in the cognitive, behavioral, and social-emotional aspects of developmental health across childhood, their early genetic and environmental determinants, as well as their putative role in later social-emotional adjustment, school, health, and occupational outcomes. A total of 662 families of twins were initially assessed when the twins were aged 6 months. These twins and their family were then followed regularly. QNTS now has 16 waves of data collected or planned, including 5 in preschool. Over the last 24 years, a broad range of physiological, cognitive, behavioral, school, and health phenotypes were documented longitudinally through multi-informant and multimethod measurements. QNTS also entails extended and detailed multilevel assessments of proximal (e.g., parenting behaviors, peer relationships) and distal (e.g., family income) features of the child’s environment. QNTS children and a subset of their parents have been genotyped, allowing for the computation of a variety of polygenic scores. This detailed longitudinal information makes QNTS uniquely suited for the study of the role of the early years and gene–environment transactions in development.

Birth weight is associated with adolescent brain development: A multimodal imaging study in monozygotic twins

“…One hundred and six 15‐year‐old MZ twins (53 pairs; 31 female pairs), mean age ± SD : 15.7 ± 0.3 years, range 15.3–16.7 years; mean BW ± SD : 2,550 ± 54 g, range 1,000–3,730 g; mean discordance ± SD : 300 ± 250 g, range 10–1,070 g) were recruited from the Québec Newborn Twin Study (QNTS; Boivin et al, 2019). The majority of the twin pairs were Caucasian (94.3%), and average maternal education ± SD at the time of birth of the twins was 12.1 ± 2.6 years.…”

“…The majority of the twin pairs were Caucasian (94.3%), and average maternal education ± SD at the time of birth of the twins was 12.1 ± 2.6 years. The QNTS recruited participants born in Québec, Canada between April 1, 1995 and December 31, 1998 through the Québec Ministry of Health and Social Services registry, and have followed them longitudinally since recruitment (Boivin et al, 2019). Zygocity was determined by analyzing eight or nine polymorphic genetic markers, and monozygocity was confirmed for those twins who were concordant for every genetic marker (Boivin et al, 2019).…”

“…The QNTS recruited participants born in Québec, Canada between April 1, 1995 and December 31, 1998 through the Québec Ministry of Health and Social Services registry, and have followed them longitudinally since recruitment (Boivin et al, 2019). Zygocity was determined by analyzing eight or nine polymorphic genetic markers, and monozygocity was confirmed for those twins who were concordant for every genetic marker (Boivin et al, 2019). Good current health was reported for all twins who underwent brain imaging, with no history of physical or psychiatric illness and no use of psychotropic medications.…”

Cognitive mechanisms underlying the associations between inattention and reading abilities

“…Participants were from the Quebec Newborn Twin Study (QNTS: Boivin et al, 2013). All parents living in the Greater Montreal area and having twin births occurring between April 1995 and December 1998 were contacted, by letter and by phone, and asked to enroll with their twins in the QNTS.…”

The Genetic and Environmental Etiology of the Association between Vocabulary and Syntax in First Grade

“…Parents of all twins born without any major complication in the greater Montreal area (Quebec, Canada) between April 1995 and December 1998 were contacted to take part in the QNTS. The twins whose parents gave their consent have been assessed annually on cognitive, behavioural, social, and environmental components of their development starting at age 6 months (initial N = 622 pairs; see Boivin et al, 2013, for more details). Ethical approval was obtained before each data collection.…”