Lack of evidence to support the glyoxalase 1 gene (GLO1) as a risk gene of autism in Han Chinese patients from Taiwan

Purpose: Previous studies have revealed inconsistent findings regarding the association between the glyoxalase 1 protein (GLO1) gene and autism. This study aimed to replicate the genetic association of the C419A of the GLO1 gene with autism and to perform mutation screening of all the exons of the GLO1 gene in a sample of Han Chinese patients with autism from Taiwan. Methods: The sample included 272 patients with autism and 310 healthy controls. All the exons and the promoter region of the GLO1 gene were PCR-amplified and sequenced for mutation screening and genotyping. Results: We did not find significant differences of allelic and genotypic frequency distributions of C419A between the autism and control groups. Moreover, we did not identify any other mutations in the exon regions associated with autism in this sample. We discovered two single nucleotide polymorphisms (SNPs) at the 5′ untranslated region of the GLO1 gene, designated g.-264T/G and g.-7T/C; however, these two SNPs were not associated with autism in this sample. Further analysis of halplotypes constructed from these 3 SNPs (g.-264T/G, g.-7T/C, and C419A) found no haplotype associated with autism. Our sample size has the power of 0.57 and 0.94 to detect a small effect (0.1) in the genotype and allele frequency distributions at the alpha level of 0.05, respectively. Conclusions: Our findings suggest that the GLO1 gene is unlikely a major susceptible gene for autism in an ethnic Chinese population from Taiwan.