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-A*01 (P = 0.03, OR 2.68), A*02 (P = 0.001, OR 3.02) and HLA-B*07 (P = 0.01, OR 3.27), were significantly associated with autism. Also, the haplotype A*02-B*07 was significantly higher in autistic patients than in controls (P = 0.007, OR 5.83). In class II, DRB1*1104 was significantly higher in patients than in controls (P = 0.001, OR 8.75). The DQB1*0202 (P = 0.001, OR 0.24), DQB1*0302 (P = 0.001, OR 0.14), and DQB1*0501 (P = 0.012, OR 0.25), were negatively associated with disease. While the four-loci genotype study showed that A*01-B*07-DRB1*0701-DQB1*0602 (P = 0.001, OR 41.9) and the A*31-B*51-DRB1*0103-DQB1*0302 (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-B*07 allele with autism. Thus, HLA-B*07 allele and the closely linked haplotype A*01 B*07 DRB1*0701 DQB1*0602 may serve as a marker for genetic susceptibility to autism in Saudis.