Association Of Vitamin D Receptor Gene BsmI Polymorphism With Developmental Dysplasia Of The Hip

ObjectiveDevelopmental dysplasia of the hip(DDH) is a common limb deformity of pediatric orthopedics.The prevalence of DDH according to racial and geographic parameters and is greater in whites than blacks.Genetic epidemiology and familial aggregation are common,which have a role in developmental dysplasia of the hip susceptibility.Because of multifactorial and overlapping pathogenetic theory,DDH is a genetically and environmentally dependent disease.The Vitamin D receptor(VDR) genotype is associated with bone mineral density,and plays an important role in cell growth and proliferation of organizations.Some studies had confirmed the relationship between VDR gene and DDH in caucasian.The main objective of this study was to investigate the relationship between VDR gene BsmI polymorphism and DDH in North Chinese Han nationality,and compared the BsmI genotype distribution in different nationality.Materials and methods1.SamplesAll the children with DDH came from department of paediatric orthopaedics, Shengjing Hospital of China Medical University.Venous blood of the patients was collected and stored at -80℃for use after anti-coagulation.2.Genotype analysisDNA was extracted from the venous blood by using QIAamp DNA Blood Mini Kit. DNA sequencing was done after polymerase chain reaction.3.Statistical analysisChi square test was used to compare the genotype distribution of VDR gene BsmI site between children with DDH and normal controls,and the difference was also analyzed in different nationality.ResultsThe genotype of VDR BsmI was detected using sequencing method.There was 1 sample of AA genotype,3 samples of AG genotype and 50 samples of GG genotype in DDH patients group.There were 2 samples of AG genotype and 53 samples of GG genotype,and no AA genotype was detected in normal individuals.No difference was found in the genotype distribution of VDR BsmI site between DDH and normal individuals.However,there was significant difference when compared the North Chinese Han nationality with caucasian.ConclusionsIn North Chinese Han nationality,the most common genotype is GG in VDR gene BsmI site,and no AA genotype was detected.The BsmI site polymorphism might not be associated with DDH in North Chinese Han nationality.