HLA-B and nasopharyngeal carcinoma: The majority of the remaining twelve moderate effect haplotypes carrying one to three MHC class I/II protective alleles of HLA-Aaa-Q62 or HLA-B loci (rs9265975/rs2523589) or HLA-DQA1 locus (rs9461780) confer 1.6- to 3.5-fold reduction of NPC risk relative to H1.