Vitamin D Receptor Polymorphisms and Nutritional Rickets in Nigerian Children

• Published in: Journal of bone and mineral research Vol. 15; no. 11; pp. 2206 - 2210
• Main Authors: Fischer, Philip R., Thacher, Tom D., Pettifor, John M., Jorde, Lynn B., Eccleshall, T. Ross, Feldman, David
• Format: Journal Article
• Language: English
• Published: Washington, DC John Wiley and Sons and The American Society for Bone and Mineral Research (ASBMR) 01.11.2000; American Society for Bone and Mineral Research
• Subjects: Adult; Africa; Biological and medical sciences; Calcium - deficiency; Case-Control Studies; Child; Deoxyribonucleases, Type II Site-Specific - genetics; dietary calcium deficiency; Fundamental and applied biological sciences. Psychology; Genetic Predisposition to Disease; Genetics of eukaryotes. Biological and molecular evolution; Human; Humans; Medical sciences; Metabolic diseases; Nigeria; Other nutritional diseases (malnutrition, nutritional and vitamin deficiencies...); Polymorphism, Genetic; Population genetics, reproduction patterns; Receptors, Calcitriol - genetics; rickets; Rickets - genetics; Tropical medicine; vitamin D receptor polymorphisms; Nigeria; Africa; Human; Calcium; Diseases of the osteoarticular system; Nutrition disorder; Vitamin deficiency; Bone disease; Inorganic element; Population genetics; Genetic determinism; Feeding; Rickets; Diet; Vitamin D; Child; Polymorphism; Biological receptor
• ISSN: 0884-0431; 1523-4681
• DOI: 10.1359/jbmr.2000.15.11.2206

Nutritional rickets is common in Nigeria where vitamin D deficiency is rare and dietary insufficiency of calcium is common. It occurs more commonly in siblings of affected children than of unaffected children. Postulating that vitamin D receptor (VDR) polymorphisms might relate to the susceptibility of some Nigerian children to develop rickets in the setting of low calcium intake, we compared the VDR genotypes, as determined by the presence or absence of Bsm I, Apa I, Taq I, and Fok I restriction enzyme cleavage sites, between 105 children with active nutritional rickets and 94 subjects representative of the community from which the rachitic children came. In the rickets group, the ff genotype was less common than in the community group, and the FF genotype was relatively increased (f allele frequency, 17% in rachitic children and 26% in the community group, p = 0.03). Neither individual allele frequencies for the other polymorphisms nor combinations of genotypes at different sites were different between the rachitic and community groups. Although it is not clear why a presumed better‐functioning VDR variant (F allele) is associated with an increased risk of developing rickets, this study raises the possibility that VDR alleles might be important in determining an individual's susceptibility to developing rickets when faced with dietary calcium deficiency.