A polymorphism at the first of two potential translation initiation codons in the vitamin D receptor (VDR) gene defined by
the
FokI restriction endonuclease has been associated with reduced bone mineral density (BMD) among Caucasian, Asian, and Mexican-American
women. We tested the hypothesis that the
FokI polymorphism is related to markers of osteoporotic risk in 104 community-dwelling African-American women aged 65 years and
older. Six percent of the African-American women had the ff genotype, 32% were heterozygous, and 63% had the FF genotype.
FokI genotype frequencies did not differ from Hardy–Weinberg expectations. Hip and calcaneal BMD, calcaneal ultrasound attenuation
and hip geometry from pelvic radiographs did not differ significantly by
FokI genotypes or between women with and without the rare
FokI allele. There was also no association between the
FokI polymorphism and biochemical markers of bone turnover or fractional calcium absorption. We conclude that the
VDR start codon polymorphism does not have a major influence on osteoporotic risk in older African-American women.
Key words:African-Americans – Bone mineral density – Genetics – Osteoporosis – Vitamin D receptor
Received: 20 November 1997 / Accepted: 29 June 1998