Estrogen plays a role in the pathogenesis of endometriosis. The CYP17 gene codes for the cytochrome P450c17α
enzyme that is involved in the estrogen biosynthesis. We aimed to investigate if CYP17 polymorphism could be used as
marker to predict the susceptibility of endometriosis. Women were divided into two groups: (1) severe endometriosis
(n=119); (2) non-endometriosis groups (n=128). A 169-bp fragment encompassing the T/C polymorphic site in 5'-
untranslated promoter region (5'-UTR) of the CYP17 was amplified by the polymerase chain reaction, treated with
restriction enzyme MspA1I, and electrophoresis. The polymorphism was divided into restriction- enzyme indigestible
(T homozygote), T/C heterozygote, and digestible (C homozygote). Genotypes and allelic frequencies for this polymorphism
in both groups were compared. We observed a higher but non-significant percentage of T homozygote in the
endometriosis women compared with the non-endometriosis women. Proportions of T homozygote/heterozygote/C
homozygote for CYP17 in both groups were: (1) 26.1/46.2/27.7% and (2) 17.2/45.3/37.5% (p- value=0.131). T allele
was related with higher susceptibility of endometriosis. T and C allele frequencies in both groups were: (1) 49.2/50.8%;
(2) 39.8/60.2% (p- value=0.046). Despite the CYP17* T allele appearing to be asscoiatd with a trend of increased risk
of endometriosis, CYP17 5'-UTR gene polymorphism might not be a useful marker for prediction of endometriosis
susceptibility.
