Shared susceptibility region on chromosome 15 between autism and catatonia

We have compiled significant linkage results from 20 genome scans for the autism syndrome disorder (ASD) and 2 for catatonia in schizophrenia (SZ). Localization of the markers has been updated across the studies using the same cytological (Genetic Location Database), physical (National Center for Biological Information), and genetic (Marshfield) maps. Eight autosomal chromosomes (1, 2, 3, 7, 9, 13, 15, and 17) showed significant linkages with ASD, and one with catatonia (15). Chromosome 15 was further characterized for SZ genome scans (N = 4) since catatonia was observed in SZ patients, for candidate genes for ASD and catatonia, and for the numerous chromosomal rearrangement and abnormalities associated to ASD. From these results, we observed that four potential susceptibility regions for ASD could be observed on chromosome 15 at 15q11-q13, 15q14-q21, 15q22-q23, and 15q26, respectively. All the four regions were shared between ASD and SZ, with 15q15-q21 being also shared with catatonia. Strong candidate genes, such as gamma-aminobutyric acid receptor B3, A5, and G3, have shown associations with ASD at 15q11-q13 susceptibility region where the majority of the chromosomal rearrangements are also found. On the other hand, negative association results were observed at 15q14-q21 susceptibility region for catatonia with the genes encoding the zinc transporter SLC30A4, the cholinergic receptor nicotinic alpha polypeptide 7, and the delta-like 4 Drosophila. Further, fine mapping and candidate gene analyses are needed to highlight potential common genes between ASD and catatonia for this chromosome.