The Relationship of HLA Class I and II Alleles and Haplotypes with Autism: A Case Control Study.

Earlier reports showed the relationship between autism and immune genes located in the human leukocyte antigen (HLA). In this current study, we compared the HLA class I and class II alleles and haplotypes in 35 autistic children with 100 control subjects from Saudi Arabia, using PCR-SSP method and Luminex technology. In class I the HLA-A01 (P = 0.03, OR 2.68), A02 (P = 0.001, OR 3.02) and HLA-B07 (P = 0.01, OR 3.27), were significantly associated with autism. Also, the haplotype A02-B07 was significantly higher in autistic patients than in controls (P = 0.007, OR 5.83). In class II, DRB11104 was significantly higher in patients than in controls (P = 0.001, OR 8.75). The DQB10202 (P = 0.001, OR 0.24), DQB10302 (P = 0.001, OR 0.14), and DQB10501 (P = 0.012, OR 0.25), were negatively associated with disease. While the four-loci genotype study showed that A01-B07-DRB10701-DQB10602 (P = 0.001, OR 41.9) and the A31-B51-DRB10103-DQB10302 (P = 0.012, OR 4.8) are positively associated with autism among Saudi patients. This is the first report on a foreseeable risk of association of HLA-B07 allele with autism. Thus, HLA-B07 allele and the closely linked haplotype A01 B07 DRB10701 DQB1*0602 may serve as a marker for genetic susceptibility to autism in Saudis.