HLA-B and autism: In order to identify HLA-B alleles associated with autism in Thai population, we compared the frequency of HLA-B allele in 364 autistic subjects with 952 normal subjects by using a two-stage sequence-specific oligonucleotide probe system (PCR-SSOP) method based on flow-cytometry technology. HLA-B⁎13:02 (P = 0.019, OR = 2.229), HLA-B⁎38:02 (P = 0.049, OR = 1.628), HLA-B⁎44:03 (P = 0.016, OR = 1.645), and HLA-B⁎56:01 (P = 1.78 × 10−4, OR = 4.927) alleles were significantly increased in autistic subjects compared with normal subjects.