[Relationship between factor VIII inhibitor development and polymorphisms of TNFα and CTLA-4 gene in Chinese Han patients with hemophilia A].

Objective: To investigate the potential association between factor VIII inhibitor development and polymorphisms of tumor necrosis factor-α (TNF-α)-308 and cytotoxic T-lymphocyte associated protein-4 gene in Chinese Han patients with hemophilia A (HA).

Methods: The single base change polymorphism in TNF-α and CTLA-4 gene was analyzed in 140 Chinese Han patients with hemophilia A who have been treated with plasma-derived FVIII concentrates and 108 normal controls by using PCR-restrictive fragment length polymorphism (RFLP). All of the HA patients' plasma samples were measured by modified-Nijmegen assay simultaneously.

Results: In HA patients, G/G genotype, G/A genotype and A/A genotype were detected in 118 (84.3%), 18 (12.8%) and 4 cases (2.9%) respectively; C/C genotype, C/T genotype and T/T genotype were detected in 108 (77.2%), 30 (21.4%) and 2 cases (1.4%) respectively. The difference in the genotype frequencies between HA patients and controls was nonsignificant (P > 0.05). Patients who were carriers of homozygotes for A allele had a higher risk of inhibitor development compared with those who were not (OR = 7.519, 95% CI = 3.168 - 17.844). Severe HA patients who were carriers of homozygotes for A allele had a higher risk of inhibitor development compared with those who were not (OR = 8.163, 95% CI = 2.521 - 26.434). There was no statistical difference in the risk of inhibitor development between the patients who were carriers or not (OR = 1.586, 95% CI = 0.729 - 3.450).

Conclusion: TNF-α-308 gene polymorphism is significantly associated with inhibitor development in Chinese Han patients with severe hemophilia A. TNF-α gene may be a useful marker and potential modulator of the immune response to replacement therapy for hemophilia A patients.