Astrocyte derived protein S100B rs9722 and rs11911834 polymorphisms and potential risk of developing major depressive disorder: a case-control study

Astrocyte-derived protein, S100B exerts neurotrophic and neuroprotective effects at physiological concentrations but may promote neuroinflammation and damage when dysregulated. Given its potential role in the pathophysiology of neuropsychiatric disorders, this study investigated the association of S100B rs9722 and rs11911834 polymorphisms with the susceptibility to major depressive disorder (MDD) in a Bangladeshi population. Blood samples were obtained from 100 MDD patients diagnosed with DSM-5 criteria and 100 healthy controls. Genotyping was performed using PCR-RFLP method followed by gel electrophoresis. Genotypes distribution for rs9722 and rs11911834 satisfied the Hardy-Weinberg equilibrium assumptions ( p > 0.05) in both groups of participants. For rs9722 polymorphism, the AA minor genotype was nominally associated with higher risk of MDD compared to the GG major genotype (aOR = 4.15, 95% CI = 1.39–10.11, adjusted p-value = 0.019). Nominal associations were also observed under allelic model (A vs. G: aOR = 1.84, 95% CI = 1.21–2.55, adjusted p-value = 0.014). However, none of these associations remained statistically significant after Benjamini-Hochberg false discovery rate (BH-FDR) correction. In contrast, no significant association was identified between rs11911834 and MDD across any evaluated genetic models. The S100B rs9722 polymorphism showed nominal associations with MDD risk under different genetic models but did not remain statistically significant after FDR correction. These findings are exploratory and may provide important insights into the underlying pathophysiology of MDD.