Genetic analysis of DSM-oriented scales in 3 year-old Dutch twins⁴

Dorret Boomsma¹, Toos van Beijsterveldt^1,2, Caroline van Baal¹, Therese Stroet¹, Tinca Polderman¹, Alexia Groot¹, Jolanda van der Valk^1,2, Frank Verhulst², Tom Achenbach³, and Jim Hudziak<sup>3

1</sup> Vrije Univ, Department Biological Psychology, Amsterdam
² Erasmus Univ, Sophia Kinderziekenhuis, Rotterdam
³ Univ of Vermont, College of Medicine, Burlington, Vermont

We collected parental ratings of behavioral and emotional problems with the Child Behavior Checklist (CBCL2-3) in a large sample of 3-year old Dutch twins (N = 6522 pairs). Mother's ratings of the twins' behavior was used to obtain the empirically-based CBCL syndrome scales. In addition, the recently developed scoring algorithm to obtain DSM-oriented scales was applied to the data (Achenbach & Rescorla: Manual for the ASEBA Preschool Forms & Profiles. Burlington, VT: Univ Vermont, Dept Psychiatry, 2000). The following DSM-oriented scales were constructed: affective and anxious problems, pervasive developmental problems and oppositional and overactive behavior. Results show high heritabilities for these DSM-oriented scales. For overactive behavior, genetic dominance is suggested; for the other scales there are small contributions of shared family environment.

⁴ Supported by Sophia Foundation SSWO 165, NWO-904-57-94 and NIH-R01 MH58799