HLA-DPB1 and acute lymphoblastic leukemia: Among our patient samples, the 4-G haplotype was moderately less frequent among BCP-ALL cases than controls (3.36 vs 4.86%; P = 0.03); this is the predominant carrier of the HLA-DPB1 allele DPB1*01∶01 (in 85% of ALL cases typed DPB1*01∶01, PHASE predicted that the allele would be carried on the 4-G haplotype) (Table 2).