Genetic Polymorphisms at TNF Microsatellites from the HLA CLASS III Region in a South Tunisian Population

To evaluate the tumor necrosis factor (TNF) a-b-c microsatellite polymorphism in South Tunisia, we studied 123 healthy unrelated controls from South Tunisia. TNF microsatellite alleles were typed using genomic DNA amplified with specific primers. Statistical analyses were performed using ARLEQUIN software. The TNFa6 (18.9%), TNFa2 (16.4%), TNFb5 (41.9%), and TNFc1 (68.7%) were the most frequent alleles in our population, whereas the TNFa8 and TNFb2 were the least frequent alleles. To investigate the association among the three microsatellites, a detailed haplotype analysis was performed. 236 different haplotypes were possible but there was only 15 haplotypes had frequencies greater than 2%. In our population the most frequent haplotype TNFcab were “TNFc1a6b5” (10.03%). These results may be informative for studies of the associations of individual TNF region markers with secretion levels, immunity, and disease.