[Study on the association of SNPs of MMP-2 and TIMP-2 genes with the risk of endometriosis and adenomyosis]

OBJECTIVE: To investigate the association of single nucleotide polymorphisms (SNPs) in matrix metalloproteinase-2 (MMP-2) and tissue inhibitor of metalloproteinase-2 (TIMP-2) with the risk of endometriosis and adenomyosis. METHODS: Genotypes of MMP-2 and TIMP-2 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method among 298 endometriosis patients, 180 adenomyosis patients and 324 matched control women. RESULTS: No significant difference was found in allele frequencies and genotype distributions of MMP-2 -1306C/T polymorphism between endometriosis patients and control women (P> 0.05). However, there were significant differences in genotype and allele distributions of MMP-2 -1306C/T polymorphism between adenomyosis patients and control women (P< 0.05). Compared with CT+TT genotypes, CC genotype significantly increases the risk of adenomyosis, with an odds ratio of 1.83 (95% CI was 1.13-2.96). No significant difference was shown in allele frequencies and genotype distributions of the MMP-2 -735C/T polymorphism among the three groups (P>0.05). MMP-2 -1306C/T and -735C/T polymorphisms displayed linkage disequilibrium (D'=0.74). There was no significant difference in haplotype distributions of the two MMP-2 SNPs among the three groups ( P> 0.05). No significant difference was found in allele frequencies of TIMP-2 -418G/C polymorphism among the three groups (P> 0.05). However, the frequency of TIMP-2 CC genotype in endometriosis patients (0.7%) was significantly lower than that in the control women (3.7%) (P< 0.05). CONCLUSION: The C allele of MMP-2 -1306C/T polymorphism did not modify the risk of developing endometriosis but significantly increase the risk of developing adenomyosis. The MMP-2 -735C/T and TIMP-2 -418G/C polymorphisms were not associated with the risk of developing endometriosis or adenomyosis.