GPx1 rs1050450 Polymorphism Modulates Selenium Status and Glutathione Peroxidase 1 Activity in Children with Autism Spectrum Disorder: A Case-Control Study from Western Algeria.

Researchers studied 75 children in Algeria and found that children with autism had lower levels of selenium (an important nutrient) and reduced activity of an antioxidant enzyme compared to typical children. They also discovered that a specific genetic variation was present in 40% of children with autism but in none of the typical children. This genetic difference may explain why some children with autism have trouble processing selenium and maintaining healthy antioxidant function.

This case-control study from western Algeria examined 75 children (35 with ASD, 40 controls) to investigate the relationship between a genetic variant (rs1050450) in glutathione peroxidase 1 (GPx1) and selenium metabolism in autism. Children with ASD showed significantly lower blood selenium levels and reduced GPx1 enzyme activity compared to controls. Notably, a specific genetic variant (TT genotype) was found exclusively in children with ASD (40% prevalence) and completely absent in controls. This genetic variant was associated with the lowest enzyme activity levels.

The study suggests that genetic differences may contribute to disrupted selenium-dependent antioxidant function in autism, potentially offering targets for personalized nutritional interventions.

Findings suggest potential for selenium testing and targeted supplementation in ASD, particularly for individuals with specific genetic variants. However, larger validation studies are needed before clinical implementation. The exclusive presence of TT genotype in ASD warrants further investigation for diagnostic and therapeutic applications.

Small sample size (75 participants), single geographic location, case-control design cannot establish causation, lacks validation in other populations, unclear if findings generalize beyond North African populations.

Oxidative stress plays a central role in autism spectrum disorder (ASD). The rs1050450 (Pro198Leu) polymorphism of glutathione peroxidase 1 (GPx1), a selenium-dependent antioxidant enzyme, may modulate selenium status and enzymatic activity. This case-control study included 75 children in western Algeria (35 children with ASD, 40 controls). Plasma selenium was quantified by voltammetry, erythrocyte GPx1 activity by spectrophotometry, and rs1050450 genotyping by PCR-RFLP.

Children with ASD exhibited significantly lower plasma selenium (49.13 ± 10.75 vs. 68.84 ± 9.48 µg/L; p < 0.001) and reduced GPx1 activity (86.73 ± 36.08 vs. 116.71 ± 35.83 U/g Hb; p < 0.05). Remarkably, the TT genotype was found exclusively in ASD children (40.0%; 14/35) with complete absence in controls (0/40), yielding χ = 18.01 (p < 0.001). The T allele was more frequent in ASD (47.1% vs. 22.5%; p = 0.003, Fisher p = 0.002). The TT genotype correlated with the lowest GPx1 activity.

Selenium-GPx1 correlations varied dramatically by genotype: negative in ASD with CC (r = - 0.555; p < 0.001) and CT (r = - 0.450; p < 0.05), positive in controls with CT (r = 0.852; p < 0.001). Parental consanguinity was more frequent in ASD (28.6% vs. 10.0%; OR = 3.60; p = 0.072). This North African cohort demonstrates hyposelenemia, reduced GPx1 activity, and exclusive TT genotype presence in ASD, suggesting converging genetic-biochemical disruptions of selenium-dependent redox homeostasis. These findings warrant validation in larger cohorts for personalized nutritional interventions.