Symptomatic and asymptomatic cases of African swine fever in Tanzania

African swine fever (ASF) is an acute, highly contagious and deadly viral haemorrhagic disease of domestic pigs caused by African swine fever virus (ASFV). In ASF endemic countries, there are an increasing number of reports on circulating ASFV strains with different levels of virulence causing a broad range of clinical symptoms in susceptible animals. Tanzania, where ASFV is endemic since 2001, recorded several outbreaks including symptomatic and asymptomatic cases between 2015 and 2017. We collected 35 clinical samples from four outbreaks for diagnostic confirmation and sequenced the partial B646L (p72), the full E183L (p54) gene, the central variable region of the B602L gene and the intergenic region between the I73R and I329L genes to characterize molecularly the new ASFV isolates and analyse their relatedness with previously reported Tanzanian and foreign isolates. We detected ASFV in 21 samples, 15 from symptomatic and six from asymptomatic pigs. Phylogenetic analyses based on the partial p72 gene and the complete p54 (E183L) genes revealed that the ASFVs in samples from symptomatic pigs belonged to genotypes II and those in samples from asymptomatic pigs belonged to genotype IX. The CVR profiles of the p72 genotype II and genotype IX isolates differed between each other and from previously published Tanzanian sequences. The sequence analysis of the intergenic region between the I73R and I329L for the 2017 genotype II isolates showed the absence of one GGAATATATA motif in those isolates. This study showed the simultaneous circulation of two different ASFV genotypes with different levels of pathogenicity in Tanzania. Since the existence of sub‐clinically infected pigs may contribute to the persistence of the virus, our findings suggest continuous surveillance and characterization of ASFV isolates in disease‐endemic regions.     

Genetic Characterization of African Swine Fever Viruses from a 2008 Outbreak in Tanzania

Outbreaks of African swine fever (ASF) have been reported in the past from several countries in sub‐Saharan Africa. The aim of this study was to genotype ASF viruses (ASFVs) from the 2008 outbreak in Morogoro and Dar es Salaam regions of Tanzania. Tissue samples from domestic pigs that died as a result of severe haemorrhagic disease were collected and analysed with PCR and genome sequencing methods using ASFV‐specific primer sets. Nucleotide sequence data were obtained for the B646L (p72), E183L (p54) and the variable region of the B602L gene sequences. Phylogenetic analyses based on DNA sequences showed that the 2008 Tanzanian isolates belonged to p72 genotype XV and clustered together with those derived from the 2001 outbreak in Tanzania. Analysis of the tetrameric amino acid repeat regions within the variable region of the B602L gene showed that the repeat signature of the 2008 Tanzanian ASFV was unique and contained three novel tetramers (U = NIDT/NTDT and X = NTDI). Epidemiological investigation suggested that transportation of live pigs continues to play an active role in the epidemiology of ASF in Tanzania. It is recommended that future control of ASF spread in Tanzania should focus on the early detection and confirmation of the disease, prompt institution of quarantine measures, culling and proper disposal of infected and in‐contact animals and decontamination of affected premises.     

Improved Strategy for Molecular Characterization of African Swine Fever Viruses from Sardinia,Based on Analysis of p30, CD2V and I73R/I329L Variable Regions

African swine fever virus (ASFV) is the aetiological agent of a highly lethal haemorrhagic disease affecting pigs that inflicts significant economic damage on the swine industry. ASF is present in many African countries, in several eastern and central European countries and in Sardinia (Italy). Sequence analyses of variable genomic regions have been extensively used for molecular epidemiological studies of ASFV isolates. Previous sequencing data of genes that codify for viral protein p54, p72 and the central variable region (CVR) within the B602L gene revealed that Sardinian isolates show a very low level of variability. To achieve a finer level of discrimination among such closely related viruses, in this study, we have chosen three different genome regions to investigate the within‐genotype relationships and to provide a more accurate assessment of the origin of outbreaks. The analysis of p30 and I73R/I329L sequences obtained from ASFV collected in Sardinia over a 13‐years period confirms a remarkable genetic stability in these regions. The sequence comparison of the protein encoded by the EP402R gene (CD2v), carried out on various strains from 1978 to 2014, revealed a temporal subdivision of Sardinian viruses into two subgroups: one group includes the historical isolates from 1978 to 1990, and the second one is comprised of the viruses collected from 1990 until 2014. These data, together with those obtained from CVR within the B602L gene analysis, demonstrated that the viruses circulating in Sardinia belong to p72 genotype I, but have undergone genetic variations in two different regions of the genome since 1990. We proposed the cytoplasmic region of CD2v protein as a new genetic marker that could be use to analyse ASFVs from different locations to track virus spread. Our study reaffirms the need to analyse other genome regions in order to improve the molecular characterization of ASFV.     

Genetic Characterization of Circulating African Swine Fever Viruses in Nigeria (2007–2015)

Sequencing and analysis of three discrete genome regions of African swine fever viruses (ASFV) from archival samples collected in 2007–2011 and active and passive surveillance between 2012 and 2015 in Nigeria were carried out. Analysis was conducted by genotyping of three single‐copy African swine fever (ASF) genes. The E183L and B646L genes that encode structural proteins p54 and p72, respectively, were utilized to delineate genotypes before intragenotypic resolution by characterization of the tetrameric amino acid repeat region within the hypervariable central variable region of the B602L gene. The results showed no variation in the p72 and p54 gene regions sequenced. Phylogeny of p72 sequences revealed that all the Nigerian isolates belonged to genotype I, while that of the p54 recovered the Ia genotype. Analysis of B602L gene revealed the differences in the number of tetrameric repeats. Four new variants (Tet‐15, Tet‐17a, Tet‐17b and Tet‐48) were recovered, while a fifth variant (Tet‐20) was the most widely distributed in the country displacing Tet‐36 reported previously in 2003–2006. The viruses responsible for ASF outbreaks in Nigeria are from very closely related but mutated variants of the virus that have been circulating since 1997. A practical implication of the genetic variability of the Nigerian viral isolates in this study is the need for continuous sampling and analysis of circulating viruses, which will provide epidemiological information on the evolution of ASFV in the field versus new incursion for informed strategic control of the disease in the country.     

Re‐emergence of genotype I of African swine fever virus in Ivory Coast

In July 2014, an outbreak of severe haemorrhagic disease in a domestic pig population, was reported in San‐Pedro, the second seaport city of Ivory Coast. Animals of all age groups developed clinical signs consistent with African swine fever (ASF). Tissue and serum samples from dead pigs were sent to the laboratory for diagnostic confirmation and molecular characterization based on the partial B646L (p72), the full E183L (p54) gene and the central variable region of the B602L gene. The PCR results confirmed the outbreak of ASF. Phylogenetic analyses based on p72 and p54 sequences showed that the San‐Pedro 2014 outbreak virus strain belongs to p72 genotype I. The Analysis of the tetrameric amino acid repeat regions of the B602L gene showed two repeat signatures which differ by an extra A = CAST in the second signature. The ASFV sequence of the San‐Pedro 2014 outbreak strain is closely related to historical and recent ASFV strains collected in Angola and Cameroon whose ships have repeatedly visited the seaport of San‐Pedro from March to June 2014. The 2014 viruses are distinct from the strains involved in the previous ASF wave in 1996 in Ivory Coast.     

Genetic characterization of African swine fever virus isolates from soft ticks at the wildlife/domestic interface in Mozambique and identification of a novel genotype

African swine fever virus (ASFV ) is one of the most threatening infectious diseases of pigs. There are not sufficient data to indicate the importance of the sylvatic cycle in the spread and maintenance of the disease locally and potentially, globally. To assess the capacity to maintain ASF in the environment, we investigated the presence of soft tickreservoirs of ASFV in Gorongosa National Park (GNP ) and its surrounding villages. A total of 1,658 soft ticks were recovered from warthog burrows and pig pens at the wildlife/livestock interface of the GNP and viral DNA was confirmed by nested PCR in 19% of Ornithodoros porcinus porcinus and 15% of O. p. domesticus . However, isolation of ASFV was only achieved in approximately 50% of the PCR ‐positive samples with nineteen haemadsorbing virus isolates recovered. These were genotyped using a combination of partial sequencing of the B646L gene (p72 ) and analysis of the central variable region (CVR ) of the B602L gene. Eleven isolates were classified as belonging to genotype II and homologous to contemporary isolates from southern Africa, the Indian Ocean and eastern Europe. Three isolates grouped within genotype V and were similar to previous isolates from Mozambique and Malawi. The remaining five isolates constituted a new, previously unidentified genotype, designated genotype XXIV . This work confirms for the first time that the virus currently circulating in eastern Europe is likely to have a wildlife origin, and that the large diversity of ASFV maintained in wildlife areas can act as a permanent sources of different strains for the domestic pig value chain in Mozambique and beyond its boundaries. Their genetic similarity to ASFV strains currently spreading across Europe justifies the need to continue studying the sylvatic cycle in this African country and other parts of southern Africa in order to identify potential hot spots of ASF emergence and target surveillance and control efforts.     

Infection of African swine fever in wild boar,China, 2018

On 16 November 2018, a wild boar infected with African swine fever was reported in China. The phylogenetic analysis showed that its causative strain belonged to the p72 genotype II, CD2v serogroup 8 and contained no additional tandem repeat sequences between the I73R and the I329L protein genes, which was different from previously reported strains in China.     

Identification of a New Genotype of African Swine Fever Virus in Domestic Pigs from Ethiopia

African swine fever (ASF) is an important emerging transboundary animal disease (TAD), which currently has an impact on many countries in Africa, Eastern Europe, the Caucasus and the Russian Federation. The current situation in Europe shows the ability of the virus to rapidly spread, which stands to threaten the global swine industry. At present, there is no viable vaccine to minimize spread of the disease and stamping out is the main source of control. In February 2011, Ethiopia had reported its first suspected outbreaks of ASF. Genomic analyses of the collected ASF virus (ASFV) strains were undertaken using 23 tissue samples collected from domestic swine in Ethiopia from 2011 to 2014. The analysis of Ethiopian ASFVs partial p72 gene sequence showed the identification of a new genotype, genotype XXIII, that shares a common ancestor with genotypes IX and X, which comprise isolates circulating in Eastern African countries and the Republic of Congo. Analysis of the p54 gene also followed the p72 pattern and the deduced amino acid sequence of the central variable region (CVR) of the B602L gene showed novel tetramer repeats not previously characterized.     

Single nucleotide polymorphisms near IL28B gene and response to treatment of chronic hepatitis C in hemodialysis patients

Abstract

Background: It has been shown that single nucleotide polymorphisms (SNPs) near the interleukin 28B (IL28B) gene were associated with sustained virological response following standard antivirological treatment of chronic hepatitis C. Objectives: The aim of the study was to evaluate the association between SNPs near the IL28B gene and response to the treatment of chronic hepatitis C in hemodialysis patients. Patients and methods: The study group included 24 hemodialysis patients with chronic hepatitis C routinely treated with pegylated interferon α-2?a. HCV genotype 1 was the cause of chronic hepatitis C in all study participants. Sustained virological response was determined by an assay with a sensitivity of 20?IU/mL, 6 months after completion of the antivirological treatment. The genotyping of the three most widely studied IL28B gene polymorphisms (rs12979860, rs8099917, and rs12980275) was performed in all study participants. Results: Sustained virological response was achieved in 50% of the treated patients. The treatment response was significantly associated with the CC genotype of rs12979860, TT genotype of rs8099917, and AA genotype of rs12980275 (p?=?0.003, p?=?0.009, and p?=?0.012, respectively). Conclusions: The three most widely studied SNPs near the IL28B gene were associated with sustained virological response following antivirological treatment of chronic hepatitis C in hemodialysis patients.     

Potential Increase in the Prognostic Value of p53 Mutation by Pro72 Allele in Stage I Non-Small-Cell Lung Cancer

Background  Accumulated evidence suggests that p53 function altered by its gene mutation or genetic polymorphism contributes to tumor malignancy. Association of p53 mutation and its codon 72 polymorphism with lung cancer prognosis has been extensively studied. However, the joint effect of p53 mutation and p53 codon 72 polymorphism on lung cancer prognosis remains uncertain. Methods  In the present study, 266 primary lung cancer patients were included and overall survival was calculated. Genomic DNA prepared from adjacent normal lung and lung tumor tissues was used to determine p53 codon 72 genotype and p53 mutation by polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP) and direct sequencing, respectively. Results  For all stages, neither p53 codon 72 genotype nor p53 mutation is associated with lung cancer prognosis. However, stage I patients with p53 mutation had a 1.79-fold hazard ratio [95% confidence interval (CI) 1.04–3.10] for overall survival when compared with p53 wild-type patients. Notably, stage I patients with p53 mutation and p53 codon 72 Pro/Pro genotype experienced a 2.66-fold hazard ratio (95% CI 1.21–5.85) for overall survival when compared with those with p53 wild-type and Arg/Arg genotype. An increased prognostic value was not observed in stage I patients with p53 wild-type and p53 Pro72 allele or in those with p53 mutation and p53 codon 72 Arg/Arg genotype. Conclusions  We therefore suggest that p53 codon 72 Pro allele potentially increases the prognostic value of p53 mutation in stage I non-small-cell lung cancer. Wen-Pin Chien and Ruey-Hong Wong equally contributed to this work.     

Multi‐locus sequencing reveals a novel Bartonella in mammals from the Superorder Xenarthra

The superorder Xenarthra consists of sloths, anteaters and armadillos, mammals originated from South America and currently distributed from the south of North America to the south of South America. The present study aimed to investigate the occurrence and genetic diversity of Bartonella spp. in blood and spleen samples from free‐living Xenarthra mammals in the states of São Paulo (SP), Mato Grosso do Sul (MS), Rondônia (RO) and Pará (PA). Based on a quantitative real‐time PCR (qPCR) assay, a Bartonella spp. nuoG gene fragment was detected in 1.51% (5/330) of the samples: 4 six‐banded armadillos (Euphractus sexcinctus) sampled in the MS and 1 southern tamandua (Tamandua tetradactyla) sampled in the PA. Eight sequences (5 ftsZ, 2 gltA and 1 rpoB) were obtained in the conventional PCR assays. In both phylogenetic analyses based on Bayesian and distance (SplitsTree) methods, the obtained ftsZ, gltA and rpoB sequences were positioned in a distinct clade, but related to B. washoensis. The analysis of SplitsTree and genotype networks based on B. washoensis sequences from several hosts from various localities of the world showed that the sequences of the present study were allocated in a group separated from the other sequences, indicating that they probably originated from median vectors and large numbers of mutational events. Additionally, the analyses performed by BLAST showed low percentages of identities of the sequences obtained in the present study when compared to those previously deposited in GenBank. Therefore, we propose a new Candidatus to Bartonella occurring in Xenarthra in Brazil. The present study was the first to report the occurrence of Bartonella sp. in mammals of the superorder Xenarthra in the world, and it was the first to describe a new Candidatus related to B. washoensis in Brazil.     

载脂蛋白A1、B基因多态性对非创伤性股骨头坏死发生的影响

目的:探讨载脂蛋白A1、B基因多态性对非刨伤性股骨头坏死(avascular necrosis of the femoral head,ANFH)发生的影响.方法:应用聚合酶链反应对中国北方汉族143例ANFH患者和92例正常人分别扩增含Apo AI基因启动子-75 bp和第一内舍子 83 bp及Apo B基因Eco RI、XbaI和3-VNTR的DNA片段,限制性内切酶酶切扩增产物,琼脂糖凝胶电泳分离基因多态性.结果:Apo A1基因启动子-75 bp处,ANFH患者中A/A基因型频率明显高于正常组(P＜0.01),而G/A基因型频率明显低于正常组(P＜0.01).Apo AI内舍子 83 bp位点,Apo B基因Eco RI、Xba I位点和3-VNTR区域ANFH患者组和正常组基因型及等位基因频率分布无统计学差异.结论:Apo A1基因启动子区域-75bp位点A/A型可能是非创伤性股骨头坏死易感基因之一,但未能发现Apo A1第一内舍子 83 bp位点及Apo B基因Eco RI、XbaI和3-VNTR位点多态性与非创伤性股骨头坏死发生有明显的关系.     

Systemic Besnoitiosis in a Juvenile Roe Deer (Capreolus capreolus)

Herein, we report the first incidence of systemic besnoitiosis in a male juvenile roe deer Capreolus capreolus. The animal was found dead in an area where bovine besnoitiosis is endemic and showed cachexia and multiple skin erosions in the metacarpal and metatarsal areas. Moreover, round and elevated white structures suggestive of Besnoitia spp. tissue cysts were also present. Twenty‐eight tissue samples from different anatomical locations were collected for microscopic lesion and parasite detection through histopathology and PCR. Immunohistochemistry was performed to confirm Besnoitia‐positive reaction in the tissue cysts. In addition, the identity of Besnoitia spp. in PCR‐positive tissue samples was also investigated using microsatellite (MS) markers, and the comparison of protein disulphide isomerase gene sequences (BbPDI) of B. besnoiti and B. tarandi isolated from cattle and reindeer, respectively. Besnoitia cysts were detected in the skin (several parts), respiratory and upper digestive tracts, eyes, kidney, liver, testicle, cardiac muscle and lymphoid tissue. Remarkably, the presence of tissue cysts in the brain confirmed the capacity of Besnoitia spp. to form tissue cysts in the central nervous system (CNS). Finally, the Besnoitia species detected showed the same MS genotype as B. besnoiti, and BbPDI sequences from roe deer and two B. besnoiti isolates were genetically identical throughout multiple sequence alignment. Thus, for the first time, there is evidence that roe deer might act as an intermediate host of B. besnoiti. Further molecular analyses and parasite isolations are needed to corroborate these findings.     

The influence of Lys3Asn polymorphism in the osteoprotegerin gene on bone mineral density in Chinese postmenopausal women

The objective was to identify single nucleotide polymorphisms (SNPs) in exons of the osteoprotegerin gene and to analyze the relationship between the SNPs and bone mineral density in postmenopausal women. We used polymerase chain reaction (PCR) and direct sequencing methods to identify SNPs and genotypes in 205 postmenopausal women. BMD at the lumbar spine (L_2–4) and femoral neck (FN) were measured by dual-energy X-ray absorptiometry (DEXA). Serum osteocalcin (OC), osteoprotegerin (OPG), receptor activator of nuclear factor B ligand (RANKL) and urinary N-telopeptide of type I collagen (NTx) were also measured. In exon 1 of the OPG gene, we found the Lys3Asn SNP. In 205 postmenopausal women, the Asn-allele frequency was 26.0%, and the distribution of Lys3Asn genotypes was Lys-Lys 56.6%, Lys-Asn 34.6% and Asn-Asn 8.8%, respectively. BMD at the lumbar spine (L_2–4) of the Asn-Asn genotype was significantly higher (9.5–12.6%) than Lys-Asn and Lys-Lys genotypes ( P =0.012), with evidence for an allele dose effect ( P =0.008). Results remained similar after adjustment for age and body mass index. The Lys3Asn polymorphism of the OPG gene alone accounted for 7.7% of the variance of the L_2–4 BMD in a multiple regression model. Logistic regression analysis revealed that the OPG genotype Lys-Lys had a 2.7 times (95% CI: 0.83–9.11) greater risk for osteopenia/osteoporosis than the Asn-Asn genotype. The Lys3Asn polymorphism in the OPG gene is associated with L_2–4 BMD in postmenopausal women. The Lys-allele is associated with lower BMD and an increased risk for osteoporosis.     

ATP6V1B1 mutations in distal renal tubular acidosis and sensorineural hearing loss: clinical and genetic spectrum of five families

Abstract

Distal renal tubular acidosis (DRTA) is characterized by tubular defects in urinary acidification and hyperchloremic metabolic acidosis, hypokalemia, hypercalciuria, hypocitraturia, nephrocalcinosis and nephrolithiasis. Mutations in ATP6V1B1 cause DRTA associated with sensorineural hearing loss. The objective of this multicenter study is to screen DRTA patients with sensorineural hearing loss for ATP6V1B1 gene mutations and present genotype/phenotype correlation. Clinical data in five unrelated consanguineous families with DRTA and hearing loss were obtained in Turkey. For mutation screening, all coding exons of ATP6V1B1 were PCR-amplified and sequenced from genomic DNA. In our cohort of five families, there were four different homozygous ATP6V1B1 mutations in affected individuals: c.91C>T (p.R31X), c.232G>A (p.G78R), c.497delC (p.T166RfsX9) and c.1155dupC (p.I386HfsX56). Our study shows that rare and family-specific variants in ATP6V1B1 are responsible for DRTA and sensorineural hearing loss syndrome in Turkey. While firm genotype–phenotype correlations are not available, detailed clinical and molecular analyses provide data to be used in genetic counseling.     

Expression of inducible lymphocyte costimulatory molecules in human renal allograft

Background: CTLA-4/CD28-B7 and CD40-CD40L interactions constitute two key costimulatory pathways in lymphocyte signalling during experimental allograft rejection. Studies on the expression of these molecules in human transplant rejection are still lacking. Methods: The immunohistochemical study was performed on renal biopsies obtained for various clinical complications from 25 renal transplant patients. Expression of B7-1 and B7-2 and their counter-receptor CTLA-4, and of CD40 and its counter-receptor CD40L was examined. Results: In acute rejection a focal intense infiltration of B7-1⁺ and B7-2⁺ cells (mainly CD20^- CD14⁺) and of CTLA-4⁺ T lymphocytes (mainly CD8⁺) was present. In contrast, CD40 and CD40L were rarely expressed. Accumulations of T lymphocytes were found in the interstitium in the same area containing B7-1⁺ and B7-2⁺ cells. The scattered CD40L⁺ cells found in the T-cell infiltrate exhibited the CD4⁺ phenotype. In chronic rejection only a few B7-1⁺, B7-2⁺ or CTLA-4⁺ cells were detectable. In contrast, several CD40L⁺CD4⁺ cells were present both in the interstitium and in glomeruli. Moreover, an intense expression of CD40 on the endothelium was observed. In patients with cyclosporin nephrotoxicity cells positive for B7-1, B7-2, CTLA-4, CD40, or CD40L were absent. Conclusions: These results demonstrate a differential expression of costimulatory molecules in renal biopsies of allograft recipients undergoing acute or chronic rejection. Moreover, their detection may prove useful to discriminate rejection from cyclosporin nephrotoxicity.     

APF, HB-EGF, and EGF biomarkers in patients with ulcerative vs. non-ulcerative interstitial cystitis

Background

Infections with high-risk human papillomaviruses (HPVs), causatively linked to cervical cancer, might also play a role in the development of prostate cancer. Furthermore, the polymorphism at codon 72 (encoding either arginine or proline) of the p53 tumor-suppressor gene is discussed as a possible determinant for cancer risk. The HPV E6 oncoprotein induces degradation of the p53 protein. The aim of this study was to analyse prostate carcinomas and hyperplasias of patients from Argentina for the presence of HPV DNA and the p53 codon 72 polymorphism genotype.

Methods

HPV DNA detection and typing were done by consensus L1 and type-specific PCR assays, respectively, and Southern blot hybridizations. Genotyping of p53 codon 72 polymorphism was performed both by allele specific primer PCRs and PCR-RFLP (Bsh1236I). Fischer's test with Woolf's approximation was used for statistical analysis.

Results

HPV DNA was detected in 17 out of 41 (41.5 %) carcinoma samples, whereas all 30 hyperplasia samples were HPV-negative. Differences in p53 codon 72 allelic frequencies were not observed, neither between carcinomas and hyperplasias nor between HPV-positive and HPV-negative carcinomas.

Conclusion

These results indicate that the p53 genotype is probably not a risk factor for prostate cancer, and that HPV infections could be associated with at least a subset of prostate carcinomas.     

检测血液p53基因SNP位点的多态性与病理性瘢痕基因型的相关性

目的探讨p53基因第72位密码子单核苷酸多态性，并分析该多态性位点与病理性瘢痕的相关性。方法常规抽取105例瘢痕患者和190例健康志愿者的血液，提取DNA，设计1对针对p53基因第4外显子第72密码子单核苷酸多态性荧光探针，进行实时定量PCR分析并观察图像。结果实时定量PCR技术检测能准确区分各种基因型，抽取295例血液样品中，基因型CCC有121例，基因型CGC有88例，基因型CCC／CGC有86例，通过PCR荧光分子信标检测p53基因第72密码子单核苷酸多态性的方法。CCC基因型患病理性瘢痕的概率最高，病理性瘢痕患者的年龄及发病部位与基因型有无相关性尚待进一步研究。结论CCC基因型及单核苷酸多态性可能与病理性瘢痕形成相关。     

Early and Late Postmenopausal Bone Loss is Associated with BsmI Vitamin D Receptor Gene Polymorphism in Japanese Women

To determine whether vitamin D receptor (VDR) gene polymorphisms are associated with bone mineral density (BMD) and bone loss in the Japanese population, VDR BsmI RFLPs were analyzed in 191 postmenopausal Japanese women by comparing B allele and b allele DNA sequences, and a point mutation was confirmed. We examined VDR BsmI restriction fragment length polymorphism (RFLP) with an amplification refractory mutation system (ARMS) using this point of mutation. The frequency of VDR BsmI alleles in the Japanese population was significantly different from that in whites. The bb genotype was identified in 79.6%, of the subjects, the Bb genotype in 19.3%, and the BB genotype was in only 1.1%. We find no significant differences in lumbar spine baseline BMD between the bb genotype and the Bb genotype. In both early and late postmenopausal periods, serial measurements of vertebral BMD revealed that subjects with the Bb genotype lost BMD faster than those with the bb genotype (P= 0.001). We conclude that there is a significant relationship between RFLPs of BsmI VDR and the annual rates of bone loss during early and late postmenopausal periods in the Japanese population. Received: 14 May 1997 / Accepted: 9 July 1998