Assessment of SHANK3, UBE3A, Dopamine Levels, and CACNA1H Gene Expression in Autism Spectrum Disorder: A Case-Control Study

Abstract

This study investigated dopamine levels and changes in UBE3A, SHANK3, and CACNA1H gene expression in children with autism spectrum disorder (ASD) to enhance understanding of the biological changes associated with the disorder. The study was conducted at Al-Zahra Teaching Hospital in Al-Kut, Iraq, involving 50 children with ASD (40 males and 10 females), aged 3–12 years, and 25 healthy controls. Blood samples were collected from all participants. Dopamine, SHANK3, and UBE3A levels were measured using ELISA, while CACNA1H gene expression was assessed by real-time PCR. Dopamine levels were significantly lower in ASD children (26.49 ng/L) than controls (44.5 ng/L; P<0.05), whereas SHANK3 levels were significantly higher (501.24 vs. 335.82 ng/L; P<0.05). UBE3A showed a non-significant increase (6.71 vs. 5.2 ng/ml). CACNA1H expression significantly decreased to 0.04-fold compared with controls (1.0).