Molecular analysis of HLA DRB1 and DQB1 polymorphism in Italian melanoma patients.

Several studies have reported association between a variety of malignancies and human leukocyte antigens (HLA) genes. However, conflicting data have been reported on HLA association and melanoma. We report here serologic and molecular analysis by polymerase chain reaction sequence-specific primers (PCR-SSP) and PCR sequence-specific oligonucleotides (PCR-SSO) of HLA class II DRB1 and DQB1 loci in 132 patients with melanoma and 102 ethnically matched controls. Molecular typing of DQB1 polymorphism showed a significant increase of DQB1 0501 (25.0% versus 14.7%; p = 0.038). Moreover, an increase of DQB10301, which was present in 62.8% of patients and 54.9% of controls (p = 0.136), was noted. Because DQB10501 and DQB10301 are strongly linked to DRB101 and DRB111, respectively, both found increased in patients with melanoma, to look for a more stringent association with a particular allele specificity of the DR locus, we performed PCR-SSP high-resolution typing of DR1 and DR11 positive subjects. Results showed no significant difference between the frequencies of the alleles found in patients with respect to controls. Analysis of the distribution of DQB10501 and DQB10301 according to the AJCC clinical stage of the disease showed no significant difference in the frequency of these alleles between the localized and the metastatic form of the disease. However, none of the HLA class II alleles showed significant association after correction of the p value. These results indicate that HLA class II alleles may not contribute to a strong susceptibility to melanoma, at least in Italian patients.