Objective: To investigate the relationship between parathyroid hormone (PTH) gene polymorphisms and secondary hyperparathyroidism in Chinese hemodialysis (HD) patients.
Materials and methods: 210 patients in one HD unit were enrolled as the study group and 203 age-matched health subjects were enrolled as controls. PTH genotypes were determined by polymerase chain reaction and restricted fragment length polymorphisms (RFLPs) of BstBI and DraII. B and b or D and d were indicated by the presence or absence, respectively, of BstBI and DraII at restriction sites on the PTH gene. Serum iPTH levels and serum total calcium (Sca), phosphate (Sp), bone-specific alkaline phosphatase (bAlk), and aluminum (Al) levels across different genotypes were compared.
Results: When polymorphisms at the BstBI the restriction site were investigated, the patients' BB, Bb, and bb genotype frequencies were 62%, 37%, and 1%, respectively. At the DraII restriction site, the patients' DD, Dd, and dd genotype frequencies were 78%, 17%, and 5%, respectively. No significant differences were found across the three genotypes, BB, Bb, and bb, in serum Sca, Sp, bAlk, Al and iPTH levels. DraII cleavage PTH gene polymorphisms displayed a similar pattern. Patients with BBDD haplotype were not found to have significantly higher serum iPTH levels than those with other haplotypes.
Conclusion: Our study appears to indicate that PTH gene polymorphisms do not influence serum iPTH levels in Chinese HD patients.