Patrones diferenciales de distribución de los alelos y genotipos HLA-DPA1* en asociación con leucemias linfoides agudas y leucemias mieloides crónicas en pacientes del estado Zulia, Venezuela

Little is known about the relevance of the polymorphisms in the function of HLA-DP. Acute lymphoblastic leukemia (ALL) is the most frequent cancer in children and adolescents in Zulia population. Chronic myeloid leukemia (CML) is similar in adolescents, young adults and mild adults. The epidemiologic studies suggest the presence of several factors related to the susceptibility. Forty-eight patients with ALL and 48 with CML, were compared with 48 controls from The Blood Bank of Zulia State, Venezuela, all of them unrelated racially mestizos. To evaluate the positive and negative associations between HLA allele and leukemias, the HLA-DPA1 locus and HLA-DPA1*01,*02,*03 and *04 alleles were studied using PCR Olerup SSPTM (Genovision). HLA-DPA1*01:05 (RR = 3.65; P ≤ .05) and DPA1*01:06 (RR = 13.88; P ≤ .05) alleles showed a positive association with ALL. Furthermore, HLA-DPA1*01:03:01-01:03:02 (RR = 0.46; P ≤ .05), DPA1*01:07 (RR = 10; P ≤ .05) and DPA1*02:01:01-02:01:06 (RR = 0.29; P ≤ .05) were negatively associated with ALL. Moreover, HLA-DPA1*01:05 (RR = 0.08; P ≤ .05), DPA1*01:08 (RR = 0.06; P ≤ .05) and DPA1*01:09 (RR = 0.14; P ≤ .05) showed a negative association with CML. Curiously, the genotype HLA-DPA1*01:03:01-01:03:02/02:01:01-02:02:06 showed a frequency of 40.4% in controls, 8.5% in ALL patients and 64.6% in CML patients. These marked differences in the frequency of distribution of HLA-DPA1* alleles and genotypes in CML and ALL patients, probably reveals a important pathogenic differences for the two types of leukemia.