An Extended Twin-Pedigree Study of Neuroticism in the Netherlands Twin Register

• Published in: Behavior genetics Vol. 48; no. 1; pp. 1 - 11
• Main Authors: Boomsma, Dorret I., Helmer, Quinta, Nieuwboer, Harold A., Hottenga, Jouke Jan, de Moor, Marleen H., van den Berg, Stéphanie M., Davies, Gareth E., Vink, Jacqueline M., Schouten, Maarten J., Dolan, Conor V., Willemsen, Gonneke, Bartels, Meike, van Beijsterveldt, Toos C. E. M., Ligthart, Lannie, de Geus, Eco J.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.01.2018; Springer Nature B.V
• Subjects: Additives; Behavioral Science and Psychology; Bioinformatics; Clinical Psychology; Data processing; Dominance; Environmental aspects; Environmental factors; Genetic factors; Health Psychology; Heritability; Medical informatics; Neurosis; Neuroticism; Original Research; Pedigree; Psychology; Public Health; Twins; Neuroticism; Extended twin-family design; Pedigree analysis; Netherlands Twin Register; Heritability; Shared household effect; Genetic non-additivity
• ISSN: 0001-8244; 1573-3297
• DOI: 10.1007/s10519-017-9872-0

For the participants in the Netherlands Twin Register (NTR) we constructed the extended pedigrees which specify all relations among nuclear and larger twin families in the register. A total of 253,015 subjects from 58,645 families were linked to each other, to the degree that we had information on the relations among participants. We describe the algorithm that was applied to construct the pedigrees. For > 30,000 adolescent and adult NTR participants data were available on harmonized neuroticism scores. We analyzed these data in the Mendel software package (Lange et al., Bioinformatics 29(12):1568–1570, 2013) to estimate the contributions of additive and non-additive genetic factors. In contrast to much of the earlier work based on twin data rather than on extended pedigrees, we could also estimate the contribution of shared household effects in the presence of non-additive genetic factors. The estimated broad-sense heritability of neuroticism was 47%, with almost equal contributions of additive and non-additive (dominance) genetic factors. A shared household effect explained 13% and unique environmental factors explained the remaining 40% of the variance in neuroticism.