QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Purchase Article View Shopping Cart Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Bezerra, F. F. Articles by Donangelo, C. M. Search for Related Content PubMed PubMed Citation Articles by Bezerra, F. F. Articles by Donangelo, C. M.

---

Nutrient Physiology, Metabolism, and Nutrient-Nutrient Interactions

Bone Mass and Breast Milk Calcium Concentration Are Associated with Vitamin D Receptor Gene Polymorphisms in Adolescent Mothers^1,2

³ Laboratório de Bioquímica Nutricional e de Alimentos, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil 21941-909; ⁴ Instituto de Nutrição, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil 20550-900; ⁵ Laboratório de Genética Humana, Departamento de Genética, Instituto Oswaldo Cruz, FIOCRUZ, Rio de Janeiro, Brazil 21040-360; and ⁶ Sociedade Brasileira de Densitometria Óssea, Rio de Janeiro, Brazil 22050-000

^* To whom correspondence should be addressed. E-mail: donangel{at}iq.ufrj.br.

Lactation-associated bone loss has been reported in adolescent mothers. Polymorphisms in the vitamin D receptor (VDR) gene may contribute to differences in the physiologic skeletal response to lactation in these mothers. We evaluated the influence of VDR gene polymorphisms ApaI, BsmI, and TaqI on bone mass, bone and calcium-related hormones, and breast milk calcium of lactating adolescents with habitually low calcium intake. Total body bone mineral content (TBMC), total body bone mineral density (TBMD), lumbar spine BMD (LSBMD), serum hormones [intact parathyroid hormone (iPTH), 25-hydroxyvitamin D, insulin-like growth factor-I (IGF1), prolactin, and estradiol), and breast milk calcium were measured in 40 lactating Brazilian adolescents (15–18 y), and compared by VDR genotype subgroups after adjustment for calcium intake and postmenarcheal and lactational periods. TBMD and LSBMD Z scores were –0.55 ± 1.01 and –1.15 ± 1.48, respectively. LSBMD was higher (21%; P < 0.05) in adolescents with the aa genotype (n = 5) compared with those with the AA genotype (n = 7). TBMC and IGF1 were higher (23 and 50%, respectively; P < 0.05) in adolescents with tt (n = 4) than those with TT (n = 29) and Tt (n = 7) genotypes. Breast milk calcium and serum iPTH were higher (24 and 80%, respectively; P < 0.05) in adolescents with bb (n = 8) compared with those with BB (n = 21) genotype. These results indicate that bone mass and breast milk calcium are significantly associated with VDR genotypes in lactating Brazilian adolescents. Those with aa and tt genotypes had a better bone status and those with bb genotype had greater breast milk calcium.