Involvement of IL-6 and IL-1 receptor antagonist on intellectual disability

Imbalances in the regulation of pro-inflammatory cytokines have been increasingly correlated with sev-eral neurodevelopmental disorders and their role in neuronal development is being investigated. Toassess the possible influence of cytokines on the onset of intellectual disability (ID), we studied thepolymorphisms of thirteen proinflammatory cytokine genes in 81 patients and 61 healthy controls.We demonstrated a significant association of interleukin-6 (IL-6) single-nucleotide polymorphism (SNP)(-174 G/C and nt565 G/A), and interleukin-1 receptor antagonist (IL-1RA) (Mspa-I 11100) SNP with ID.Moreover, the IL-6 SNPs is an unfavorable genetic predisposition for females. The evaluation of circulat-ing levels of IL-6 and IL-1RA showed that the serum concentrations of IL-6 were significantly higher in IDpatients than in controls. These data suggest that functional cytokine gene polymorphisms may influencethe development of ID.