Independent replication and initial fine mapping of 3p21–24 in Asperger syndrome

Background: Asperger syndrome is characterised by abnormalities in social interaction as well as repetitive and stereotyped behaviours and interests. The trait is thought to display complex inheritance, but in a subset of families the inheritance resembles the autosomal dominant model. Linkage to 3p14–24 has recently been reported in Asperger syndrome in Finnish families with a maximum multipoint NPL all of 3.32 at D3S2432. Methods: We have replicated linkage findings to 3p21–24 in 12 new extended Asperger syndrome families. Linkage analyses were performed separately for the 12 new families, and linkage and association analyses were also performed jointly with data from the original genome-wide screen. Results: Best two point and multipoint logarithm of the odds (LOD) scores in analyses of both data sets were obtained at D3S2432 (NPL all  = 3.83) with both subsets of families contributing to linkage. Association analysis of the combined data set produced a trend towards association with D3S2432 and D3S1619. Conclusions: This study further validates 3q21–24 as a candidate region for Asperger syndrome.