The Heritability of Type D Personality by an Extended Twin-Pedigree Analysis in the Netherlands Twin Register

Abstract

Type D (Distressed) personality combines negative affectivity (NA) and social inhibition (SI) and is associated with an increased risk of cardiovascular disease. We aimed to (1) validate a new proxy based on the Achenbach System of Empirically Based Assessment (ASEBA) for Type D personality and its NA and SI subcomponents and (2) estimate the heritability of the Type D proxy in an extended twin-pedigree design in the Netherlands Twin Register (NTR). Proxies for the dichotomous Type D classification, and continuous NA, SI, and NAxSI (the continuous measure of Type D) scales were created based on 12 ASEBA items for 30,433 NTR participants (16,449 twins and 13,984 relatives from 11,106 pedigrees) and sources of variation were analyzed in the ‘Mendel’ software package. We estimated additive and non-additive genetic variance components, shared household and unique environmental variance components and ran bivariate models to estimate the genetic and non-genetic covariance between NA and SI. The Type D proxy showed good reliability and construct validity. The best fitting genetic model included additive and non-additive genetic effects with broad-sense heritabilities for NA, SI and NAxSI estimated at 49%, 50% and 49%, respectively. Household effects showed small contributions (4–9%) to the total phenotypic variation. The genetic correlation between NA and SI was .66 (reflecting both additive and non-additive genetic components). Thus, Type D personality and its NA and SI subcomponents are heritable, with a shared genetic basis for the two subcomponents.

Major Depressive Disorder and Lifestyle: Correlated Genetic Effects in Extended Twin Pedigrees

“…Also of interest is that few twin and family studies of MDD report estimates of non-additive effects (D), whereas we find roughly equal additive and non-additive genetic contributions to the broad-sense heritability (making up 18.9% and 14.6% of total phenotypic variance, respectively). Similar increases in non-additive genetic effects have been reported in extended twin pedigree designs for other traits (e.g., [40,57,58]), and may result from increases in statistical power or the ability to model additional variance components. We note that the inclusion of non-twin family relations introduces age differences within relative pairs, which might mimic non-additive effects when, for example, age differences result in reduced resemblance in parent-offspring pairs, but not in DZ twin or sibling pairs (Table 1).…”

Genetic and environmental contributions to stability and change in social inhibition across the adolescent and adult life span.

“…Social inhibition was assessed by the social inhibition subscale of the recently validated ASEBA-based proxy questionnaire for components of type D personality using the Netherlands Twin Registry adult twin-family dataset (Li-Gao et al, 2021). Identical items (“ I have trouble making or keeping friends,” “ I would rather be alone than with others ,” “ I am secretive or keep things to myself ,” “ I am too shy or timid, ” “ I keep from getting involved with others, ” and “ Others do not like me ”) were derived from the adult self-report (ASR) and the Young Adult self-report form (YASR; Li-Gao et al, 2021). ASR/YASR is well-validated instrument, which is part of the Achenbach System of Empirically Based Assessment (ASEBA) taxonomy (Achenbach et al, 2017), and consists of items assessing adaptive functioning and problems.…”

“…The scores on the SI scales range between 0 and 12, with a higher score indicating greater social inhibition. The previous study on the adult sample from the Netherlands Twin Register showed that the SI scale (based on ASR) was valid and had good internal consistency (Li-Gao et al, 2021). We additionally assessed internal consistency of the SI scale at the younger ages (based on YASR) by calculating McDonald’s omega (Hayes & Coutts, 2020).…”

“…It has previously been demonstrated in another large Dutch cohort that the ASR and YASR scales may validly be used in concert for comparison across the adolescent and adult life span (Barzeva et al, 2019). The SI construct comprised four items from the withdrawn scale, and two interpersonal sensitivity items from the social problems subscale (Li-Gao et al, 2021). Each item was Common Terminology in Behavior Genetics rated on a 3-point Likert scale from 0 (never), 1 (sometimes), to 2 (often).…”