Age of Onset in Schizophrenia Spectrum Disorders: Complex Interactions between Genetic and Environmental Factors

In this study we evaluated the role of a candidate gene for major psychosis, Sialyltransferase (ST8SIA2), in the risk to develop a schizophrenia spectrum disorders, taking into account exposure to stressful life events (SLEs). Eight polymorphisms (SNPs) were tested in 94 Schizophreniainpatients and 176 healthy controls. Schizophrenia patients were also evaluated for SLEs in different life periods. None of the SNPs showed association with schizophrenia. Nevertheless, when crossing genetic variants with childhood SLEs, we could observe trends of interaction with age of onset. Though several limitations, our results support a protective role of ST8SIA2 in individuals exposed to moderate childhood stress.

Association Analyses of ST8SIA2 Genetic Polymorphisms with Schizophrenia in the Korean Population

OBJECTIVES: ST8SIA2 (ST8 alpha-N-acetyl-neuraminide alpha-2, 8-sialyltransferase 2 gene) is located at 15q26, a susceptibility locus for schizophrenia. Some previous research had indicated that single-nucleotide polymorphisms (SNPs) in the promoter region of ST8SIA2 were associated with schizophrenia in Japanese and Chinese populations. We investigated the association between SNPs in the promoter region of ST8SIA2 and schizophrenia in the Korean population. METHODS: The study subjects were 190 Korean patients with schizophrenia and 190 healthy controls. We performed allelic, genotypic, and haplotypic association analyses for rs3759916, rs3759915 and rs3759914 of ST8SIA2. All genotypes were determined by direct sequencing. RESULTS: In the genotype-based analysis, rs3759914 showed a nominally significant association with schizophrenia under recessive genotypic model (p = 0.047). However, this association did not remain statistically significant after correction for multiple testing. Both allelic and haplotype analyses did not show any significant association. CONCLUSIONS: These findings suggest that ST8SIA2 does not play a major role in the susceptibility to schizophrenia in the Korean population. Further studies with a larger number of subjects are required to definitively rule out minor effects of this gene on schizophrenia vulnerability.