Genetic validation study of protein tyrosine phosphatase receptor type D (PTPRD) gene variants and risk for antipsychotic-induced weight gain.

Schizophrenia is a severe, debilitating disorder with a lifetime prevalence of 1% irrespective of gender or ethnicity and is typically treated with antipsychotic drugs. Antipsychotic-induced weight gain (AIWG) is a leading factor of patient non-compliance and has previously been shown to increase the risk of type 2 diabetes, metabolic syndrome, and cardiovascular events. The current study intends to replicate findings from a recent genome-wide association study in Han-Chinese patients implicating two gene variants (rs10977144 and rs10977154) of the protein tyrosine phosphatase receptor type D (PTPRD) in antipsychotic-induced weight gain (AIWG). We investigated a sample of European and African American ancestry (n = 201) and calculated percentage of weight change using linear regression corrected for type of antipsychotics, duration of treatment and principal components from ancestry checks. As secondary goal, we investigated additional gene variants of PTPRD previously not associated with AIWG. We found no association with rs10977144 and rs10977154. However, we found nominally significant results between PTPRD and AIWG with rs73398242 in Europeans (BETA = - 0.267, p = 0.002) and rs13294608 in African Americans (BETA = 0.423, p = 0.003). According to Haploreg, both SNPs are histone marks for enhancers and promoters across various brain regions including the cingulate gyrus and dorsolateral prefrontal cortex. In summary, our results tentatively suggest that PTPRD might be associated with AIWG although different SNPS might be involved in different ethnic groups.