Estrogen receptor gene polymorphism in Japanese patients with multiple sclerosis

Estrogen has been reported to have immunosuppressive functions, and to inhibit the progression of experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). Since estrogen shows its biological effects via estrogen receptors (ER), we investigate the possible role of ER genes (ERG) in the pathogenesis of MS. PvuII and XbaI polymorphisms in ERG were detected by PCR-RFLP from the DNA of 79 conventional MS patients and 73 healthy controls. The [P] allele in the profiles in PvuII was significantly more prevalent in MS patients than in the controls (P<0.0005). In the study of XbaI polymorphism, the onset age of MS patients with the Xx genotype was earlier than that of the xx genotype group (mean age+/-S.D.; 22.60+/-8.04, and 27.49+/-9.14, respectively) (P<0.05) by ANOVA followed by Fisher's PLSD. Although the Xx genotype group tended to earlier onset age than the XX genotype group (29.60+/-11.10), this difference did not reach. On the basis of these results, PvuII polymorphism might be associated with susceptibility to MS, and XbaI polymorphism with onset age of MS. ERG polymorphism should be further studied in other populations to improve strategies for treatment of MS.