Polymorphisms in the Promoter and Coding Regions of the Synapsin III Gene

The human synapsin III gene, located on chromosome 22q12–13, has previously been reported to indicate a susceptibility for schizophrenia. Noval rare variants (Thr136Thr in exon 3, Pro468Ser, Glu525Gln and Pro534Leu in exon 12, and 1769 G/C in the untranslated region of exon 13) were found in addition to the polymorphic variant (–196 G/A in the promoter region). No significant differences in genotypic or allelic frequencies of the –196 G/A polymorphism were found between 87 unrelated schizophrenic patients and 100 healthy controls, even when the patients were diagnostically subdivided into subtypes and course specifiers. Furthermore, allelic frequencies of the GATG repeat in intron 1 were not significantly different between the patients and the controls. These results suggest that synapsin III gene polymorphisms are not associated with schizophrenia.