Genotipificacion del gen HLA DQB1 en diabetes autoinmune del adulto (LADA) / [HLA DQB1 genotyping in latent autoimmune diabetes of adults (LADA)]

ABSTRACT

Autoimmune diabetes is a complex, multifactorial disease caused by the interaction of genetic and environmental factors. This autoimmune diabetes is commonly manifested in childhood and adolescence with a fast onset (type 1 diabetes, IDDM) and it can occur in adult patients with a slow onset with delayed insulin requirement, (latent autoimmune diabetes in adults, LADA ). Autoimmune diabetes has strong class II HLA association mainly with DQB gene which constitutes the first susceptibility locus. However, association with the 5INS- VNTR and CTLA-4 genes has been established. In this study, we analysed the polimorphic allele frequencies of DQB HLA gene in 63 LADA patients, 70 IDDM and 79 control subjects. The HLA DQB1 alleles typing was detected through Olerup SSP DQ kit using sequence specific primers. We observed a positive association of *0201-*0302 and *0201-*0201 genotypes in both types of diabetic patients compared to the control group (p < 0.05). Moreover, *0201-*0302 genotype was higher in IDDM than in LADA (p < 0.05). On the other hand, the *0602 protective allele analysis showed a high prevalence in the normal group compared to the diabetic population. In Argentina, the most frequent allele of susceptibility in LADA and IDDM patients was the *0201. Summing up, the finding of an increase in the *0201 allele, both in allelic and genotypic frequencies, allows the characterisation of our population of patients, LADA and IDDM, unlike other populations, in which the most frequent allele is *0302.