Objective: To investigate the distribution of parathyroid hormone (PTH) gene polymorphisms and the relationships of PTH gene polymorphisms with bone mass and serum bone relative biochemical markers.
Methods: Blood samples of 314 normal female volunteers, aged 20 - 80, were collected. Serum PTH, bone alkaline phosphatase (sBAP), cross-linked N-telopeptide of collagen type I (sNTX), cross-linked C-telopeptide of collagen type I (sCTX), osteoprotegerin (OPG) and leptin were determined by ELISA. Polymorphisms of PTH gene were detected by polymerase chain reaction fragment length polymorphisms (PCR-RFLP) of restriction enzyme BstBI. BMD (QDR4500A) of the anteroposterior spine (AP), supine lateral spine (Lat), and femoral neck (FN) were measured.
Results: (1) The genotype frequency of BB, Bb, and bb were 75.8%, 23.3% and 0.9% respectively in normal females volunteers. The frequencies of RFLP alleles B and b were 87.5% and 12.5% respectively. There was no difference in the polymorphism frequency of PTH gene between the post- and pre menopausal women. (2) There were no significant differences in the BMD of the AP, Lat, and FN and the serum biochemical markers between the BB and Bb genotypes. (3) Multiple stepwise regression analysis showed that PTH did not influence the BMD values.
Conclusion: PTH gene polymorphism has no relationship with bone mass and serum bone biochemical markers in normal females.