MOLECULAR ANALYSIS OF HLA DRB1 AND DQB1 POLYMORPHISM IN ITALIAN MELANOMA PATIENTS

Several studies have reported association between a variety of maligna ncies and human leukocyte antigens (HLA) genes. However, conflicting d ata have been reported on HLA association and melanoma. We report here serologic and molecular analysis by polymerase chain reaction sequenc e-specific primers (PCR-SSP) and PCR sequence-specific oligonucleotide s (PCR-SSO) of HLA class II DRB1 and DQB1 loci in 132 patients with me lanoma and 102 ethnically matched controls. Molecular typing of DQB1 p olymorphism showed a significant increase of DQB10501 (25.0% versus 1 4.7%; p = 0.038). Moreover, an increase of DQB10301, which was presen t in 62.8% of patients and 54.9% of controls (p = 0.136), was noted. B ecause DQB10501 and DQB1*0301 are strongly linked to DRB1*01 and DRB1 11, respectively, both found increased in patients with melanoma, to look for a more stringent association with a particular allele specifi city of the DR locus, we performed PCR-SSP high-resolution typing of D R1 and DR11 positive subjects. Results showed no significant differenc e between the frequencies of the alleles found in patients with respec t to controls. Analysis of the distribution of DQB10501 and DQB1*0301 according to the AJCC clinical stage of the disease showed no signifi cant difference in the frequency of these alleles between the localize d and the metastatic form of the disease. However, none of the HLA cla ss II alleles showed significant association after correction of the p value. These results indicate that HLA class II alleles may not contr ibute to a strong susceptibility to melanoma, at least in Italian pati ents.