Possible association of combined vitamin D receptor and estrogen receptor genotypes and low bone mineral density in Jordanian postmenopausal women.

The genetics of osteoporosis has been extensively studied over the last 20 years. Many of the studies have been aimed at identifying possible risk factors and possible association with low bone mineral density (BMD). Vitamin D receptor (VDR) and estrogen receptor (ER) gene polymorphisms were the first to be studied. Some studies have shown a possible association for individual VDR and ER or combined VDR and ER genotypes in some populations, and others showed lack of such an association. This study is aiming at identification of a possible association with low BMD in Jordanian postmenopausal women. We used restriction fragment length polymorphisms (RFLPs) to study four polymorphisms in the VDR gene and two polymorphisms in the ER gene. Our sample was composed of 100 normal controls and 120 samples from patients with symptomatic vertebral fractures. The results showed a possible association of the ppxx genotype with low BMD in controls and patients and an association of the AaBbTT genotype with high BMD in control subjects. The AABBTT, AABBTTFF, and AABBTTFFPPXX genotypes showed a possible association with low BMD in patients. Further studies are needed to confirm the last finding since it could be an important predictor of low BMD in the Jordanian population.