title: Vitamin D receptor gene variability as a factor influencing bone mineral density in pediatric patients.
abstract: To determine the relationship between the polymorphism of vitamin D receptor gene and the bone mineral density in children. The study group consisted of 395 children aged 6-18 years. All patients underwent genotyping using the PCR-RFLP method within polymorphic loci BsmI (rs1544410), FokI (rs2228570), ApaI (rs7975232) and Taq I (rs731236) of the VDR gene. The BMD (g/cm(2), Z score) and BMC (g, Z score) by DXA method, as well as Z scores of the BUA, SOS and Stiffness ultrasound parameters were evaluated. Based on densitometry results, children were divided into 3 groups: I-Z score ± 1.0; II-Z score from -1.1 to -2.0; and III-Z score ≤ -2.1. A control group numbering 294 children was used for the purpose of allele frequency comparisons. The occurrence of studied polymorphism alleles in the control group did not significantly differ from the values expected according to the Hardy-Weinberg equilibrium (p values: 0.1224 for BsmI; 0.5958 for TaqI; 0.0817 for ApaI; and 0.8901 for FokI). Allele a ApaI carrier status in group III children was associated with an increased BMD (x = 0.8 vs 0.69, p = 0.0296) and BMC value (x = 28.76 vs 22.14, p = 0.0565) in spine projection results, Stiffness (x = -1.12 vs -1.91, p = 0.0347) and SOS (x = -1.43 vs -2.27, p = 0.0319) ultrasound parameters. In group II, significantly increased SOS values (-1.13 vs -1.73, p = 0.0378) were noted in f (FokI) carriers. The presence of aa                         ApaI and ff                         FokI polymorphisms favours a higher bone mass and better bone structure (decreased bone mass loss) in the analysed group.
authors.affiliation: Department of Paediatric Propedeutics and Bone Metabolism Diseases, Medical University of Lodz, ul Sporna 36/50, 91-738, Łódź, Poland. propedeutyka@usk4.umed.lodz.pl
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Jakubowska-Pietkiewicz
authors.forename: Wojciech
authors.initials: W
authors.lastname: Młynarski
authors.forename: Izabela
authors.initials: I
authors.lastname: Klich
authors.forename: Wojciech
authors.initials: W
authors.lastname: Fendler
authors.forename: Danuta
authors.initials: D
authors.lastname: Chlebna-Sokół
mesh_terms: D000293:Adolescent; D000483:Alleles; D015519:Bone Density / Q000235:genetics*; D002648:Child; D003720:Densitometry; D005260:Female; D014644:Genetic Variation; D006579:Heterozygote; D006801:Humans; D008297:Male; D018167:Receptors, Calcitriol / Q000235:genetics*; D014463:Ultrasonography
chemical_list: D018167:Receptors, Calcitriol