Effect of Cdx2 Polymorphism on the Relationship between Dietary Calcium Intake and Peak Bone Mass in Young Japanese Women

Abstract

Studies investigating the effect of the caudal-type homeobox protein 2 (Cdx2) polymorphism in the vitamin D receptor gene and calcium intake on bone mass have shown inconsistent results. This study investigated whether the effect of calcium intake on peak bone mass is affected by Cdx2 polymorphism in young Japanese women. A cross-sectional study of 500 young women was conducted. Dietary intake was assessed by the Food Frequency Questionnaire. The osteo sono-assessment index (OSI), assessed by the qualitative ultrasound method, was used as a bone mass index. The subjects were divided into two groups by the median calcium intake. The OSI was not different among Cdx2 genotypes and between calcium groups (p = 0.960, p = 0.191, respectively). The interaction between calcium and Cdx2 genotypes on the OSI approached significance (GG versus GA and AA genotypes, p = 0.092). The difference in the OSI between calcium groups was significant in the GG genotype (p = 0.028), but not in the GA or AA genotypes (p = 0.501, p = 0.306, respectively). Adjustment for covariates (body mass index and physical activity) did not change the results. In conclusion, the relationship between dietary calcium intake and peak bone mass may vary according to Cdx2 polymorphism.

Variante no gene receptor da vitamina D e sua relação com a fibromialgia

“…Ao que diz respeito sobre as variantes genéticas desse gene sabe-se que cinco são as mais conhecidas: FokI, BsmI, TaqI, ApaI e Cdx2, cada um localizado em uma região do gene e associado a alterações diferentes do receptor, podendo aumentar ou diminuir sua atividade. O polimorfismo Cdx2, por exemplo, é resultado da substituição de uma guanina por uma adenina na região promotora do gene, levando a transição do alelo G para o alelo A e com isso há um aumento da atividade transcricional do gene (Pulito et al, 2015;Valdiveso & Fernandez, 2006;Oono et al, 2020).…”

Relationship between vitamin D receptor gene polymorphisms (BsmI, TaqI, ApaI, and FokI) and calcium intake on bone mass in young Japanese women

“…The present study evaluated the VDR genotypes, bone mass, and calcium intake in young Japanese women. As we have previously elucidated the relationship between bone mass and Cdx2 (rs11568820), a representative SNP of VDR genes [ 32 ], the present study focused on four representative VDR gene polymorphisms other than Cdx2 , including Bsm I (rs1544410), Taq I (rs731236), Apa I (rs7975232), and Fok I (rs2228570).…”

“…We previously reported that the relationship between dietary calcium intake and bone mass differs depending on the VDR Cdx2 genotype [ 32 ]. Furthermore, certain studies have implied that VDR genotypes modulate the calcium absorption rate [ 42 – 44 ].…”

Relationship Between Vitamin D Receptor Gene polymorphisms (BsmI, TaqI, ApaI, and FokI) and Calcium Intake on Bone Mass in Young Japanese Women

“…From our previous study, it was reported that the relationship between the VDR Cdx2 genotype and bone mass differs depending on dietary calcium intake (28). Furthermore, certain studies have implied that VDR genotypes modulate the calcium absorption rate (38)(39)(40).…”