Abstract: BACKGROUND ＆ AIM: To study the relationship between CR1 genomic density polymorphism of erythrocyte with the quantitative expression of ECR1 and immune functions in patients with Non_Hodgkin Lymphoma. MATERIALS AND METHODS: ECR1 gene in erythrocytes was measured with PCR_RFLP method.Expression level of ECR1 was assessed by the quantitative assay. Soluble CD4, CD8 levels in serum were detected by ELISA. The RBC_C3bRR, RBC_ICR and TRR levels in erythrocyte were detected by the method established by Guo Feng. RESULTS: Expression of ECR1 gene in erythrocytes of Non_Hodgkin Lymphoma patients was markedly lower than that in normal persons(P<0.01), but HL type and LL type were markedly higher than that of normal people(P<0.01). The expression level of ECR1 of Non_Hodgkin Lymphoma patient was markedly lower than normal persons(P<0.01). There was positive correlation between CR1 genomic density polymorphism and expression level of ECR1 in erythrocytes and lymphocytic immune function. CONCLUSION：There was positive correlation between CR1 genomic density polymorphism with expression level of ECR1 in erythrocyte and immune function in the body. That could affect the prognosis of patients with Non_Hodgkin.

Key words: lymphoma, Non_Hodgkin, CR1, polymorphism, immune