[Estrogen receptor gene polymorphism and its association with clinicopathological manifestation of lupus nephritis]

To investigate the distribution of estrogen receptor (ER) in patients with lupus nephritis (LN), and the association between ER gene polymorphism and the clinical and pathological features of the disease.

The Pvu II and Xba I restriction fragment length polymorphism (RFLP) of estrogen receptor gene were analyzed in 245 biopsy proven LN patients (58 males and 187 females) and 172 normal controls(101 males and 71 females) by PCR-RFLP. The clinical and pathological features of 49 male and 152 female LN patients with genotype PpXx or Ppxx, ppxx were then analyzed respectively.

It was found that genotype PpXx and ppxx, Ppxx were three major genotypes of ER gene in both lupus patients group and control group. The distribution of ER gene polymorphism was quite different in lupus patients of different genders. The frequency of the PpXx genotype was significantly higher in male LN patients than in both the gender matched normal controls (P<0.05) and the female LN patients (P<0.05), while no difference was shown in the frequency of PpXx genotype between female LN patients and female controls. Interestingly, varied clinical and renal pathological features were also demonstrated in female patients with different genotypes of ER gene.

The distribution of ER gene polymorphism in LN patients varies with gender. The PpXx genotype of ER gene may be associated with the susceptibility of LN in male. ER gene polymorphism is probably one of the genetic factors contributing to the development of clinical heterogeneity and sexually dimorphic manifestations of LN.