Roles and regulation of bone morphogenetic protein-7 in kidney development and diseases

The gene encoding bone morphogenetic protein-7(BMP7) is expressed in the developing kidney in embryos and also in the mature organ in adults. During kidney development, expression of BMP7 is essential to determine the final number of nephrons in and proper size of the organ. The secreted BMP7 acts on the nephron progenitor cells to exert its dual functions: To maintain and expand the progenitor population and to provide them with competence to respond to differentiation cues, each relying on distinct signaling pathways. Intriguingly, in the adult organ, BMP7 has been implicated in protection against and regeneration from injury. Exogenous administration of recombinant BMP7 to animal models of kidney diseases has shown promising effects in counteracting inflammation, apoptosis and fibrosis evoked upon injury. Although the expression pattern of BMP7 has been well described, the mechanisms by which it is regulated have remained elusive and the processes by which the secretion sites of BMP7 impinge upon its functions in kidney development and diseases have not yet been assessed. Understanding the regulatory mechanisms will pave the way towards gaining better insight into the roles of BMP7, and to achieving desired control of the gene expression as a therapeutic strategy for kidney diseases.

Expression of Vascular Endothelial Growth Factor in Bone Morphogenetic Protein-2 Induced Osteogenesis

An experimental model of femoral muscular pouch in 20 mice was adopted. The expression of VEGF was examined by in situ hybridization method and immunohistochemical method in bone morphogenetic protein- 2 induced osteogenesis . The experimental results demonstrated that the expression signals of VEGF mRNA and VEGF appeared in cytoplasm during condensation of mesenehymal cell. As the mesenchymal cells differentiated into precartilage, the expression signals decreased in mesenehymal cells, but increased in chondrocytes and kept getting denser in the process of cartilage maturity. The peak expression of VEGF mRNA and VEGF in the experimental group appeared on the 14 th day, accompanied by numerons hypertrophic chondrocytes. When mature cartilage calcified and neu, bone trabecula formed, the expression of VEGF mRNA and VEGF decreased in chondrocytes, but still expressed moderately in the osteoblasts and osteocytes. Signals of VEGF mRNA and VEGF can not be detected in the control groups.

Bone marrow mesenchymal stem cells with Nogo-66 receptor gene silencing for repair of spinal cord injury

We hypothesized that RNA interference to silence Nogo-66 receptor gene expression in bone marrow mesenchymal stem cells before transplantation might further improve neurological function in rats with spinal cord transection injury. After 2 weeks, the number of neurons and BrdU-positive cells in the Nogo-66 receptor gene silencing group was higher than in the bone marrow mesenchymal stem cell group, and significantly greater compared with the model group. After 4 weeks, behavioral performance was signiifcantly enhanced in the model group. Af-ter 8 weeks, the number of horseradish peroxidase-labeled nerve ifbers was higher in the Nogo-66 receptor gene silencing group than in the bone marrow mesenchymal stem cell group, and signiifcantly higher than in the model group. The newly formed nerve ifbers and myelinated ner ve ifbers were detectable in the central transverse plane section in the bone marrow mesenchymal stem cell group and in the Nogo-66 receptor gene silencing group.

Effect of Bone Marrow Mesenchymal Stem Cells Transfected with rAAV2-bFGF on Early Angiogenesis of Calvarial Defects in Rats

The purpose of this study was to evaluate the effect of bone marrow mesenchymal stem cells (MSCs) transfected with the basic fibroblast growth factor (bFGF)-expressing recombinant adeno-associated virus vector (rAAV2-bFGF), on early angiogenesis of calvarial defects in rats. The MSCs were cultured and transfected with rAAV2-bFGF after differential adherence isolation. The transfection efficiency was detected by RT-PCR and Western blotting. The transfected MSCs were compounded with poly-DL-lactide/hydroxyapatite (PDLLA/HA) in vitro. The cranial defect models in 36 male SD rats were created. Nothing (group A), PDLLA/HA alone (group B), PDLLA/HA combined with MSCs (group C), and PDLLA/HA combined with rAAV2-bFGF transfected MSCs (group D) were implanted in rat calvarial defects. The specimens were harvested for hematoxylin-eosin staining on the day 1, 3 and 7 after implantation. Factor Ⅷ immunohistochemical staining and histomorphometric analysis were carried out to evaluate neovascularization around the implantation. The results indicated that MSCs could indeed be successfully transfected with the rAAV2-bFGF vector. Histological and histomorphometric analysis revealed that the angiogenesis in group D was significantly enhanced as compared with the rest groups (P<0.05). These results strongly suggest that MSCs transfected with rAAV2-bFGF in combination with PDLLA/HA can effectively promote the early angiogenesis of calvarial defects in rats, which played an important role in creating an environment suitable for the survival and activity of transplanted cells for further applications in cranio-maxillofacial bone regeneration.

The study of migration of bone mesenchymal stem cells transplanted in intervertebral discs of rabbits and expression of exogenous gene

Objective： To explore the survival and migration of bone mesenchymal stem cells transplantated in intervertebral disc of rabbits and expression of the exogenic genes. Methods. Thirty-two rabbits were used, A randomized block design was used and discs in the same rabbit were one block,the lumbar discs from L2-3 to L5-6 were randomly divided into blank group, saline group, cell transplantation group Ⅰand cell transplantation group Ⅱ. The fluorescence microscopy was used to determine the fluorescence of the maker protein GFP and DNA-PCR was used to analyze the copies of DNA of neomycin-resistant gene at 1, 3, 6, months after transplantation. Results： There was fluorescence in cell transplantation group Ⅰ and Ⅱ and none in blank group, saline group at 1, 3, 6 months after transplantation. In cell transplantation groups,the fluorescent distribution was more scatter with time, but no significant difference between cell groups Ⅰ and Ⅱ. The test of neomycin resistant gene expressed in cell transplantation group Ⅰ and Ⅱ and quantitative analysis showed that there was no significant difference between the cell groups Ⅰ and Ⅱ （P〉0.05）. Conclusion： The transplanted bone mesenchymal stem cells can survive, migrate and the transfer genes can express efficiently, it suggests that the BMSC therapy may be effective to prevent and treat intervertebral disc degeneration.

Brain-derived neurotrophic factor genes transfect rat bone marrow mesenchymal stem cells based on cationic polymer vector

BACKGROUND： Gene therapy is an effective expression of genes within target cells after transferring exogenous target genes. Both vector selection and transfection method are important factors for gene transfection. An ideal gene vector is required for a high transfusion of target gene and an exact introduction of target gene into specific target cells so as to express gene products. OBJECTIVE： To study the expression of mRNA and protein after transfecting rat bone marrow mesenchymal stem cells （BMSCs） with brain-derived neurotrophic factor （BDNF） genes based on cationic polymer vector. DESIGN, TIME AND SETTING： A randomized, controlled in vitro study using gene engineering, performed at the Neurobiology Laboratory, Xuzhou Medical College between October 2007 and April 2008. MATERIALS： PcDNA3.1 BDNF was obtained from Youbiai Biotechnological Company, Beijing and cationic polymer vector used was the SofastTM gene transfection reagent that was made by Taiyangma Biotechnological Co., Ltd., Xiamen. METHODS： BMSCs extracted from six Sprague Dawley （SD） rats aged 1 month were isolated and cultured in vitro. Third passage BMSCs were inoculated on a 6-well culture plate at the density of 1×106 cells/L. At about 80% confluence, BMSCs were transfected with PcDNA3.1-BDNF （2 μg） combined with SofastTM gene transfection reagent （6 μg） （BDNF group） or with PcDNA3.1 （2 μg） combined with SofastTM gene transfection reagent （6 μg） （blank vector group）. Cells that were not transfected with any reagents but still cultured under primary culture conditions were used as a non-transfection group. MAIN OUTCOME MEASURES： Enzyme linked immunosorbent assay was used to measure time efficiency of BMSC-secreted BDNF protein. Twenty-four hours after gene transfection, RT-PCR was used to detect expression of BDNF mRNA in the BMSCs. Immunohistochemistry was used to determine expression of BDNF protein in the BMSCs. RESULTS： BDNF protein expression was detected at day 1 after gene transfection, rapidly increased after 5–9 days and gradually increased after 11–15 days in the BDNF group; moreover, BDNF protein expression was higher than that in the non-transfection group and the blank vector group at different time points （P 〈 0.01）. Additionally, BDNF mRNA expression in the BDNF group was higher than that in the blank vector group and the non-transfection group （P 〈 0.01）. CONCLUSION： A cationic polymer vector can effectively mediate the BDNF gene to transfect BMSCs; genetically modified BMSCs can express BDNF protein effectively for a long term.

Gene expression profiles associated with osteoblasts differentiated from bone marrow stromal cells

Objective:To study the changes of gene expression profiles associated with osteoblasts differentiated from rat bone marrow stromal cells in vitro by gene chip technique.Methods:rat Rone marrow stromal cells were isolated and cultured,and differentiation was induced by dexamethasone,β-glycerol phosphate and vitamin C.Cellular mRNA was extracted and reverse transcribed into cDNA,thus related genes expression differences were detected by gene expression profile chip.Results:Calcifying nodules were visible in the induced cells.There were27.7%genes expressed differentially,three times more than the normal and induced cells,and some genes were related to transcription,translation,glycosylation modification.Extracellular matrix,signal molecules and metabolism were up—regulated.Conclusions:The gene chip technique can be used to detect the multi-gene different expression in the differentiationinduceed rat BMSCs,and these differentially expressed genes are necessary genes related to rat BMSCs proliferation and induction of osteoblastic differentiation.

Adenovirus-mediated human brain-derived neurotrophic factor gene-modified bone marrow mesenchymal stem cell transplantation for spinal cord injury

Rat bone marrow mesenchymal stem cells expressing brain-derived neurotrophic factor were successfully obtained using a gene transfection method, then intravenously transplanted into rats with spinal cord injury. At 1,3, and 5 weeks after transplantation, the expression of brain-derived neurotrophic factor and neurofilament-200 was upregulated in the injured spinal cord, spinal cord injury was alleviated, and Basso-Beattie-Bresnahan scores of hindlimb motor function were significantly increased. This evidence suggested that intravenous transplantation of adenovirus- mediated brain-derived neurotrophic factor gene-modified rat bone marrow mesenchymal stem cells could play a dual role, simultaneously providing neural stem cells and neurotrophic factors.

Construction of Adeno-associated Virus System for Human Bone Morphogenetic Protein 7 Gene

To construct the recombinant adeno-associated virus （rAAV） vector with human bone morphogenetic protein 7 （BMP7） and observe the BMP7 mRNA expression in vitro, BMP7 CDS sequence was cloned into expression plasmid pAAV-MCS of AAV Helper Free System. The recombinant plasmid was identified with enzyme digestion and sequencing. The recombinant plasmid, pAAV-RC, pHelper were co-transfected into AAV-293 cells according to the calcium phosphate-based protocol. The viral stock was collected by 4 rounds of freeze/thaw. After purified and concentrated, the recombinant virus titer was determined by dot-blot assay. HEK293 cells were transfected with the recombinant virus at different MOI, and the expression of BMP7 mRNA was detected by RT-PCR. The results showed rAAV-BMP7 was constructed and packaged successfully. The physical particle titer was 2.5×10^11 vector genomes/mL. There was different expression level of BMP7 mRNA after transfecton. These data suggested that recombinant AAV mediated a stable expression of hBMP7 mRNA in 293 cells. The AAV production method may pave the way of an effective strategy for the jaw bone defection around dental implants.

Bone Morphogenetic Protein 15 as a Candidate Gene for Prolificacy of Jining Grey Goat

On the basis of the ovine bone morphogenetic protein 15(BMP15)gene,two pairs of primers(PI and P2)were designed to amplify exons 1 and 2 of the BMP15 gene in five randomly selected does of both Angora and Jining Grey goats.The sequences of BMP15 exon 1(P1 amplification)of Angora and Jining Grey goats were identical.There was a 3-nucleotide(CTT)insertion in positions 268 to 270 of goat BMP 15 exon1 compared with that of sheep(GenBank accession number AF236078),which caused a leucine insertion in the 12th position of amino acid sequence.Sequence length of goat BMP 15 exon 2(P2 amplification)was identical with that of sheep(AF236079),but there were seven nucleotide and four amino acid changes between goat and sheep.The nucleotide in the 963rd position of BMP15 exon 2 was A for Angora goat and sheep,and G for Jining Grey goat.Based on this A963G mutation,primer pair P3 was designed to detect single nucleotide polymorphism of BMP15 exon 2 in breeds of high prolificacy(Jining Grey),moderate prolificacy(Boer)and low prolificacy(Angora and Inner Mongolia Cashmere)by polymerase chain reactionsingle strand conformation polymorphism(PCR-SSCP).Three genotypes(AA,AG and GG)were detected in Jining Grey goats,two genotypes(AG and GG)in Boer,and only the AA genotype in Angora and Inner Mongolia Cashmere goats.Sequencing revealed one mutation(A963G)in genotype GG compared with genotype AA,and this mutation resulted in an amino acid change of serine→glycine(S300G).In Jining Grey goats,frequencies of AA,AG and GG genotypes were 0.008,0.059 and 0.933,respectively.Genotypic distributions of the BMP 15 gene were significantly different(P<0.05 or P<0.001)between Jining Grey and Boer,Angora,and Inner Mongolia Cashmere goats.In Jining Grey goats,the does with the GG genotype had 0.71(P<0.05)or 1.57(P<0.05)additional kids than did those with AG or AA genotypes,and does with the AG genotype had 0.86(P<0.05)more kids than did those with the AA genotype.These results tentatively indicate that the BMP15 gene is either a major gene that affects prolificacy in Jining Grey goats,or may be a molecular marker in close linkage with such a gene.

Inhibitory effects of cytosine deaminase gene-transfected bone marrow mesenchymal stem cells on glioma cell proliferation

Bone marrow mesenchymal stem cells were isolated from C57BL mice, transfected with the cytosine deaminase （CD） gene using a lentivirus vector and co-cultured with C6 glioma cells to verify anti-tumor effects of bone marrow mesenchymal stem cells carrying CD genes. C57MSC-CD/eGFP cells converted 5-fluorocytosine to 5-fluorouracil and exhibited significant inhibition of proliferation and apoptosis in C6 glioma cells. C57MSC-CD/eGFP cells were then implanted into rat models of brain C6 glioma. Rats were also intraperitoneally injected with 5-fluorocytosine after 7 days. MSC-CD/eGFP cells were irregularly distributed at the margin of the glioma, as well as encased and reduced the volume of the glioma. CD-transfected bone marrow mesenchymal stem cells inhibit the in vivo growth and in vitro proliferation of glioma.

Association of Bone Turnover Levels with MTHFR Gene Polymorphisms among Pregnant Women in Wuhan, China

Pregnancy is a critical stimulator of bone mineral resorption. We used to find the MTHFR gene polymorphisms are related with blood lead levels among pregnant women. Pregnancy-stimulated bone turnover may be associated with MTHFR gene polymorphisms too. In this article, we aimed to determine the relationship between MTHFR gene polymorphisms and bone turnover rates among the pregnant women. The participants including pregnant and non-pregnant women were selected and recruited during their routine prenatal or physical examination from July to October in 2012. A total of 1000 participants, including 250 pregnant women in the first, second, and third trimesters and 250 non-pregnant women, were enrolled in the study. Finally, after excluding 27 participants unable to provide blood samples, 973 eligible participants （i.e., 234, 249, and 248 pregnant women in the first, second, and third trimesters, respectively, and 242 non-pregnant women） were included in the research. The MTHFR gene 1298CC homozygote carriers were more susceptible to yield higher plasma homocysteine levels than the 1298AA/AC carriers, with standardized coefficients of 0.086 （P〈0.05） and 0.104 （P〈0.01） of all the participants and the pregnant women, respectively. The MTHFR gene 1793AA homozygote carriers more likely showed higher plasma osteocalcin levels （standardized β=0.091, P〈0.01） than the 1793GG/GA carriers among all the subjects. Plasma homocysteine levels were positively correlated with blood lead levels among the participants and the pregnant women with standardized coefficients of 0.320 （P〈0.01） and 0.179 （P〈0.01）, respectively. Plasma osteocalcin levels were positively associated with blood lead levels among pregnant and non-pregnant women with standardized coefficients of 0.084 （P〈0.05） and 0.125 （P〈0.01）, respectively. In conclusion, homocysteine and osteocalcin contents in plasma are associated with the MTHFR gene A1298C polymorphism and blood lead levels among pregnant women. The MTHFR gene A1298C polymorphism-related homocysteine is a possible risk factor for increased blood lead levels among Chinese women.

Gene expression and cellular localizations of tumor necrosis factor-α at the site of implanted bovine cancellous bone in mice

The objective of this study was to determine if mRNA encoding for tumor necrosls factor-α(TNFα) was present at the site of implanted bovine cancellous bone and to observe the cellular localizations. The particles of bovine cancellous bone treated by special chemical reagents were implanted in the mouse’s muscle pouch. removed 5.10 and 20 days after implantation, and the specimens were processed for determining the expression and cellular localizations of TNFα mRNA, which was performed by a nonradioactive in situ hybridization technique. The results showed that (1) 5, 10 and 20 days after transplantation, the TNFα mRNA expressions were positive, andthe positive rate of expression was the highest by 10 days (P<0. 05 ). (2)There was strong hybridization signal localization to the nuclei of morphologically ldentifiable monocytes and multinucleated giant cells. (3)Similar activity was detected in the cytoplasm and (or) nuclei of partial adjacent mesenchymal cells, fibroblasts as well as striated muscle fibers. This finding tended to indicate that mRNA encoding for TNFα was intensely expressed in several kinds of cells and that TNFα seemed to be of importance for the modulation of local cellular immunity in the region of implanted xenogeneic bone.

Osteogenic Potential of Cultured Bone Marrow Stromal Cells Transfected with Transforming Growth Factor β_1 Gene in vitro

To study the osteogenic potential of cultured bone marrow stromal cells transfected with transforming growth factor β 1 gene in vitro , cultured BMSCs were transfected with the complexes of pcDNA 3 TGF β 1 and Lipofectamine Reagent in vitro . The cell proliferation was detected by MTT method and the morphological features of transfected BMSCs was observed. ALP stains and PNP method were used to measure ALP activity. In addition, the collagen type Ⅰ propeptides and mineralized matrixes were examined by immunohistochemical staining and tetracycline fluorescence labeling respectively. The morphological and biological characters of the transfected BMSCs were similar to those of osteoblasts and the cell proliferation was promoted. The cell layer displayed strong positive reaction for ALP stains and immunohistochemical staining. ALP activity and collagen type Ⅰ expression increased remarkably after transfection. Mineralized matrixes formed earlier and more in transfected BMSCs as compared with control group. It is concluded that transfecting with TGF β 1 gene could promote the osteogenic potential of cultured BMSCs.

Molecular Cloning and Sequence Analysis of FullLength cDNA Encoding Human Bone Morphogenetic Protein—7

Objective:To clone the full-length human bane morphogenetic protein-7 (BMP-7 ) gene and analyse its sequence, to aid in investigation of its function and structure. Methods : Total RNA was isolated from Chinese fetal kidney by the acid gmnidinium thiocyanate phenol-chloroform method. Two overlapping segments of human BMP- 1 cDNA were obtained by reverse transcription (RT)-PCR. Following application, the two segments were ligated to each other and subcloned into POEM-T easy vector to form PEGM-T easy/hBMP-7 recombinant plasmid. Sanger dideoxy chain-termination method was used to sequence the cDNA. Results. There was 750 bp fragment obtained RT-PCR using #2 primer from 5' end of BMP-7 gene (PCR by using # 2 and # 1) ,and 540 bp fragment from 3' end was generated by KT-PCR using # 4 primer (PCR using # 3 and # 4). Full-length cDNA encoding BMP-7 was obtained by religation of two segments. When compared with hBMP-7 sequence in Gene bank (XM30619) ,our full-length BMP-7 cDNA has a G instead of a T at nucleotide 862. This change results in valine substituting for phenylalanine in the protein. Conclusion. This is the first time that BMP-7 cDNA was successfully cloned from Chinese fetal kidney. BMP-7 cDNA plays an important role in healing injuries of the osteo-articular system. This makes BMP-7 is an attractive target far various clinical applications.

Establishment and identification of fibroblast clones expressing human bone morphogenetic protein 2

Objective:To establish fibroblasts stably expressing human bone morphogenetic protein 2(hBMP2). Methods:Eukaryonic expression vector(pcDNA3.1-B2) was transduced into NIH3T3 cells using SofastTM, a new generation cationic polymer gene transfection reagent. The positive cell clones were selected with G418. The stable transfection and expression of BMP2 in the NIH3T3 cells were determined by RT-PCR and immunohistochemical stain. Results: BMP2 mRNA was transcripted and expressed in the transfected NIH3T3 cells. Conclusion: With positive compound transfection, outside human BMP2 gene can be successfully transducted into NIH3T3 cells, which is the key step to induce periodontal cells to osseous phenotypes.

An experiment study of osteogenesis of Ad-VEGF165 transfected human bone marrow mesenchymal stem cells in vitro

Objective ：To evaluate the effect of osteogenic potential on human marrow mesenchymal stem cells （hMSCs） transferred with human vascular endothelial growth factor（VEGF） gene by adenovirus, methods：hMSCs were isolated from human marrow, cultured in vitro and randomly divided into 3 groups ：Ad-VEGF165 group： adding 1×10^10 OPU/ml Ad-VEGF in hMSCs culture fluid after incubating 24 hours, changing into ordinary complete culture and continuing culturing; Positive control group： Cultured hMSCs with 1 nmol/L dexamethasone, 10 mmol/L glycerophosphate and 50 mg/L vitamin C ,exchanging this conditioned medium twice a week; blank control group：no special treatment but culturing hMSCs in DMEM.To evaluate osteogenesis competence, Von Kossa＇s staining and a quantitative alkaline phosphates （ALP） activity analysis were performed after 2 weeks treatment. Results：The calcified nodes formed after 2 weeks treatment in Ad-VEGF165 group and Positive control group but not in blank control group. ALP activities in Ad-VEGF165 group ,Positive control group and blank control group were （7.91 ± 0.90）u/L, （8.18 ± 0.76 u/L） and （3.46 ± 0.49）u/L respectively. The differences were no statistical significance between Ad-VEGF165 group and positive control group （P 〉 0.05）, but Ad-VEGF165 group and Positive control group were significantly different with blank control group （P 〈 0.05）. Conclusion：Adenovirus mediated VEGF165 gene can transfect hMSCs and promote osteogenesis of hMSCs.

Effects of NPY Gene on Total Number of Eggs at 300 Days of Age in Donglan Black-bone Chicken

In this study, PCR-RFLP technique was employed to detect the genetic polymorphism of NPY gene and analyze the effects of various genotypes on the total number of eggs at 300 days of age in 135 Donglan black-bone chicken. According to the results, there were three genotypes （AA, AB and BB） of NPYgene in Donglan black-bone chicken group. Different genotypes exhibited significant effects （P 〈 0. 05 ） on the total number of eggs at 300 days of age. The total number of eggs at 300 days of age of AA genotype was significantly higher than that of BB genotype （P 〈 0. 05）. Therefore, the polymorphic site of NPY gene could be used as a candidate molecular marker that affects egg laying in Donglan black-bone chicken.

Cloning, expression profiling and promoter functional analysis of bone morphogenetic protein 2 in the tongue sole(Cynoglossus semilaevis)

BMP2 plays crucial roles in vertebrate developmental process and acts as a bone inducer during osteogenesis. We present here the molecular cloning of bmp2 cDNA from the marine flatfish Cynoglossus semilaevis, and the analysis of bmp2 expression profiling and promoter function. The full length of bmp2 cDNA sequence is 2 048 bp,which encodes a protein of 422 amino acids. Tissue expression distribution of bmp2 was examined in 14 tissues of mature individuals by quantitative real time PCR（qRT-PCR）. The results revealed that bmp2 was expressed ubiquitously, and the highest expression level was detected in the spinal cord. Moreover, bmp2 expression levels were detected at 15 sampling time points of early developmental stages（egg, larva, juvenile and fingerling stages）.The highest expression level of bmp2 was observed at the gastrula stage, which was about ten times higher than those at the other three embryo stages. Whole-mount in situ hybridization showed that the bmp2 signal was strongly detected at the location of the crown-like larval fin, heart and liver, and slightly expressed in the notochord at one day post hatch（dph）; then the expression of bmp2 started to be concentrated in notochord at three dph. Subsequently, we characterized the 5′-flanking region of bmp2 by testing the promoter activity by Luciferase reporter assays. Positive regulatory region was detected at the location of –179 to ＋109. The predicted transcription factor binding sites（E-box binding factors, zinc finger transcription factor, etc.） in this region might participate in the transcriptional regulation of the bmp2 gene.

ASSOCIATION OF PARATHYROID HORMONE GENE POLYMORPHISM WITH BONE MINERAL DENSITY IN CHINESE WOMEN

Objective.To investigate the distribution frequency of parathyroid hormone(PTH)gene polymorphism in healthy adults from Bejing area and to explore the association of PTH genotypes with bone mineral density(BMD).Methods.PTH gene polymorphism was detected in270subjects by polymerase chain reaction(PCR)and PCR /restriction fragment length polymorphism(PCR /RFLP).The digestion products of restriction enzyme Bst B1were separated on1%agarose gels.PTH genotypes were confirmed by DNA sequences analysis.BMD was measured by dual-energy X-ray absorptiometry(DEXA,DPX -L ,Lunar).Results.Genotype frequencies of BB,Bb,bb were73.7%,25.9%and0.4%respectively in Beijing adults(P<0.01),67.1%,32.2%and0.7%in postmenopausal women,which was different from Japanese wom-en.We statistically compared bone mineral density at the lumbar2-4and proximal femur between BB and Bb genotypes.No obvious association was found between the BMD and PTH genotypes in Beijing women(P>0.05).Conclusion.PTH gene polymorphism is not associated with BMD in Chinese women.The further research to explore the genetic risk factors of osteoporosis should be committed.