This study sought to elucidate the role of the Pvull and Xbal polymorphisms of the estrogen receptor gene in 74 Chinese patients with multiple sclerosis,and 95 ethnicity-matched controls.using polymerase chain reaction-restriction fragment-length polymorphism analysis.The results revealed that the P allele of Pvull was significantly more prevalent in multiple sclerosis patients compared with controls(P=0.019).While distribution frequencies were significantly increased in female multiple sclerosis patients compared with female controls(P=0.044),no significant difference was observed between male patients and controls(P>0.05).Frequencies of Ppxx genotypes were significantly higher in multiple sclerosis patients compared with controls(24.3%VS.12.8%,P=0.025).Genotypes and alleles of the estrogen receptor were not associated with age.number of attacks or expanded disability status scale scores of patients with multiple sclerosis.These findings jndicate that the PVUll but not the Xbal polymorphism in the estrogen receptor gene iS associated with susceptibility to multiple sclerosis in the Chinese population.in addition.women with P allele appear to be particularly susceptible to multiple sclerosis.