Replication of a ROBO2 polymorphism associated with conduct problems but not psychopathic tendencies in children

The co-occurrence of conduct problems (CPs) and high callous–unemotional (CU) traits specifies risk for adult psychopathy and is under a high genetic influence. A previous genome-wide pooled DNA study of 7-year olds identified a set of candidate single-nucleotide polymorphisms (SNPs) that might differentiate high CPCU children from healthy children. We attempted to replicate an identified subset of these SNP–psychopathy associations. In a case–control design, 210 clinically referred children were partitioned into Comparison, High CPLow CU, and High CPCU groups and genotyped. One SNP, rs13064369, differentiated the groups but was associated with high CP, regardless of the level of CU traits, that is, the rare and heterozygote variants CC and CT were significantly more frequent in both CP groups compared with Comparisons but did not differ from each other. We replicated the finding that a polymorphism associated with the ROBO2gene, which is involved in neurodevelopment, confers risk for the common emotionally reactive, impulsive aspects of conduct disorder, independent of concurrent risk for psychopathy.