Tumor necrosis factor-α(TNF-α), a proinflammatory cytokine, plays an important role in the process of autoimmune diseases. p53 is related to the regulation of cell growth and prevention of carcinogenesis. We propose to investigate whether gene polymorphisms for TNF-α-308 promoter and p53 could be used as markers of susceptibility in leiomyomas. Prospective basic study. Departments of gynecology and genetics in a medical center. Group 1: leiomyoma (n = 159); group 2: nonleiomyoma (n = 131). Genomic DNA was obtained from peripheral leukocyte. The TNF-αand p53 gene polymorphisms were amplified by polymerase chain reaction (PCR), enzyme restriction, and electrophoresis. Two gene polymorphisms were identified: [1] the A (cuttable)/G (uncuttable) polymorphisms of the TNF-αgene on chromosome 6p21.3; [2] A (cuttable)/P (uncuttable) polymorphisms of the p53 gene on chromosome 17p. Genotype and allelic frequencies in both groups were compared. Genotype distribution and allele frequency of TNF-α.gene polymorphism in both groups were significantly different. Proportions of A homozygote/heterozygote/G homozygote for TNF-α.in both groups were: (group 1) 61%/34.6%/4.4%and (group 2) 81.7%/14.5%/3.8%. Proportions of allele A/G for TNF-αin both groups were: (group 1) 78.3%/21.7%and (group 2) 88.9%/11.1%. Distributions of p53 polymorphisms in both groups were not different. The proportions of A homozygotes/heterozygotes/P homozygotes for p53 were (group 1) 32.7%/42.1%/25.2%and (group 2) 28.2%/48.9%/22.9%. G homozygote and G allele for TNF-αpromoter are related to a higher risk of leiomyomas. The p53 codon 72 gene polymorphism is not associated with the susceptibility of leiomyomas. Tumor necrosis factor-alpha (TNF-alpha), a proinflammatory cytokine, plays an important role in the process of autoimmune diseases. P53 is related to the regulation of cell growth and prevention of carcinogenesis. We propose to investigate whether gene polymorphisms for TNF- α-308 promoter and p53 could be used as markers of susceptibility in leiomyomas. Prospective basic study. Departments of gynecology and genetics in a medical center. Group 1: leiomyoma (n = 159); group 2: nonleiomyoma The TNF-α and p53 gene polymorphisms were amplified by polymerase chain reaction (PCR), enzyme restriction, and electrophoresis. Two gene polymorphisms were identified: [1] the A (cuttable) / G uncuttable) polymorphisms of the TNF-α gene on chromosome 6p21.3; [2] A (cuttable) / P (uncuttable) polymorphisms of the p53 gene on chromosome 17p. Genotype and allelic frequencies in both groups were compared. o f TNF-α.gene polymorphism in both groups were significantly different. Proportions of A homozygote / heterozygote / G homozygote for TNF-α.in both groups were: 61% / 34.6% / 4.4% and (group 2) 81.7% / 14.5% / 3.8%. Distributions of allele A / G for TNF-αin both groups were: 78.3% / 21.7% and (group 2) 88.9% / 11.1%. Distributions of p53 polymorphisms in both groups were not different. The proportions of A homozygotes / heterozygotes / P homozygotes for p53 were (group 1) 32.7% / 42.1% / 25.2% and (group 2) 28.2% / 48.9% / 22.9%. G homozygote and G allele The TNF-αpromoter are related to a higher risk of leiomyomas. The p53 codon 72 gene polymorphism is not associated with the susceptibility of leiomyomas.