Analysis of codon 72 polymorphism of the TP53 gene in infertile women with and without endometriosis

PURPOSE: to evaluate the frequency of TP53 codon 72 polymorphism in infertile women with endometriosis, women with idiopathic infertility, controls and its relation to the disease. METHODS: a case-control study that included 198 infertile women with endometriosis, 70 women with idiopathic infertility and 169 fertile women without endometriosis as control. Detection of TP53 codon 72 gene polymorphism (rs1042522, Arg/C:Pro/G), that promotes a C/G exchange in the coding region of the gene, was performed by real time Polymerase Chain Reaction (PCR), using the TaqMan system of primers, that flank the implicated region and probes labeled with different fluorescent dyes, one for allele C and other for allele G. When two dyes were observed, the patient was considered to be heterozygous CG. In the presence of only one dye, the individual was considered to be homozygous CC or GG. The chi(2) test was used to compare allele and genotype frequencies between groups. All p-values were two-tailed and a p-value <0.05 was considered to be statistically significant. RESULTS: we found no statistically significant difference in the distribution of TP53 codon 72 polymorphism genotypes CC, CG or GG (p=0.7) and alleles C or G (p=0.4) between infertile patients with endometriosis and controls (p=0.4), regardless of the stage of the disease. In relation to infertility, no statistically significant difference in the genotype or allele distribution (p=1.0 and p=0.9, respectively) was observed between idiopathic infertile women and controls. Considering the dominant inheritance model, again, no statistically significant difference was found even in the endometriosis (p=0.5) or the idiopathic infertility group (p=0.9) when compared to controls. Regarding the recessive inheritance model no statistically significant difference was found, with p=0.6 and p=1.0, respectively, for the endometriosis and idiopathic infertility groups. CONCLUSION: the results suggest that the TP53 codon 72 polymorphism does not confer genetic susceptibility to endometriosis and/or infertility in the Brazilian population, not even the severe form of the disease.