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1.
2.
Single nucleotide polymorphisms in the protamine-1 and -2 genes of fertile and infertile human male populations 总被引:6,自引:0,他引:6
Tanaka H Miyagawa Y Tsujimura A Matsumiya K Okuyama A Nishimune Y 《Molecular human reproduction》2003,9(2):69-73
Although various genetic factors have been implicated in human male infertility, the causative genes for the different types of idiopathic male infertility have not been elucidated. Protamines, which are the major DNA-binding proteins in the sperm nucleus, package the DNA into the sperm head. Analysis of the human protamine-1 (PRM1) and -2 (PRM2) gene sequences in 226 sterile male patients and in 270 proven-fertile male volunteers revealed four single nucleotide polymorphisms (SNPs) in the PRM1 coding region, which did not cause any amino acid substitutions, and one SNP in the PRM2 gene, which produced translation termination. We also observed one SNP in the 3' non-coding region of the PRM1 gene, and two SNPs within the intron of the PRM2 gene. The prevalence of these SNPs was similar in both infertile patients and in proven-fertile volunteers, except that the c248t alteration in the PRM2 gene induced a nonsense codon under conditions of heterozygosity in one infertile patient. Although the PRM1 and PRM2 genes are highly conserved, the single SNP in the PRM2 gene that induces translation termination may result in male infertility due to haploinsufficiency of PRM2. 相似文献
3.
Watanabe T Imoto I Kosugi Y Fukuda Y Mimura J Fujii Y Isaka K Takayama M Sato A Inazawa J 《Journal of human genetics》2001,46(6):342-346
The diversity of biological effects resulting from exposure to dioxin may reflect the ability of this environmental pollutant
to alter gene expression by binding to the arylhydrocarbon receptor (AHR) gene and related genes. AHR function may be regulated by structural variations in AHR itself, in the AHR repressor (AHRR), in the AHR nuclear translocator (ARNT), or in AHR target molecules such as cytochrome P-4501A1 (CYP1A1) and glutathione S-transferase. Analysis of the genomic organization
of AHRR revealed an open reading frame consisting of a 2094-bp mRNA encoded by ten exons. We found one novel polymorphism, a substitution
of Ala by Pro at codon 185 (GCC to CCC), in exon 5 of the AHRR gene; among 108 healthy unrelated Japanese women, genotypes Ala/Ala, Ala/Pro, and Pro/Pro were represented, respectively,
by 20 (18.5%), 49 (45.4%), and 39 (36.1%) individuals. We did not detect previously published polymorphisms of ARNT (D511N) or the CYP1A1 promoter (G-469A and C-459T) in our subjects, suggesting that these polymorphisms are rare in the Japanese population. No
association was found between uterine endometriosis and any polymorphisms in the AHRR, AHR, ARNT, or CYP1A1 genes analyzed in the present study.
Received: January 24, 2001 / Accepted: March 1, 2001 相似文献
4.
Gender-specific haplotype association of collagen α2 (XI) gene in ossification of the posterior longitudinal ligament of the spine 总被引:5,自引:0,他引:5
Maeda S Koga H Matsunaga S Numasawa T Ikari K Furushima K Harata S Takeda J Sakou T Komiya S Inoue I 《Journal of human genetics》2001,46(1):1-4
Among Japanese, ossification of the posterior longitudinal ligament of the spine (OPLL) is a leading cause of myelopathy,
showing ectopic bone formation in the paravertebral ligament. We have provided genetic evidence that the collagen α2 (XI)
(COL11A2) locus of chromosome 6 constitutes susceptibility for OPLL. Five distinct single nucleotide polymorphisms (SNPs), identified
in COL11A2, were combined to construct possible haplotypes by the use of a maximum likelihood program. Estimated haplotype frequency
was compared in OPLL patients and non-OPLL controls. We report a gender-specific association of the COL11A2 haplotype with OPLL. The frequency of the most commonly observed haplotype was significantly higher in male patients (P = 0.0003) compared with controls, but not in female patients (P = 0.21). OPLL is predominantly observed in males, with a prevalence ratio of 2 : 1, and our gender-specific associations
indicate that genetic factors involving COL11A2 play a specific role in the etiology of OPLL exclusively in males.
Received: September 5, 2000 / Accepted: October 2, 2000 相似文献
5.
IFN-α以抗病毒及免疫调节双莺作用用于慢性乙型肝炎的治疗,对治疗反应的早期预测有利于治疗的持续.随着人类基因组学和蛋白质组学的研究进展,国内外对HBV感染发病及治疗反应遗传易感因素有较多报道,主要集中于抗病毒蛋白和免疫调节相关细胞因子的基因多态性.此文就遗传易感因素对IFN-α治疗慢性乙型肝炎疗效的影响作了综述. 相似文献
6.
Confirmation of genetic variants associated with lethal prostate cancer in a cohort of men from hereditary prostate cancer families 下载免费PDF全文
Qianchuan He Laura McIntosh Jonathan L. Wright Elaine A. Ostrander Ziding Feng Janet L. Stanford 《International journal of cancer. Journal international du cancer》2015,136(9):2166-2171
Germline genetic variants have been suggested as prognostic biomarkers for identifying patients at high risk for lethal prostate cancer (PCa). Validation studies have confirmed the association of several single nucleotide polymorphisms (SNPs) with fatal PCa, but whether these variants affect PCa‐specific mortality (PCSM) in patients with an inherited predisposition to PCa, based on familial history, is unknown. For this study, a cohort of 957 PCa patients from 270 hereditary prostate cancer families of European ancestry was genotyped for a panel of 22 PCSM‐associated SNPs. Death certificates were reviewed to confirm cause of death. Mixed‐effect Cox proportional hazards models were used to assess survival according to genotypes, accounting for relatedness and clinicopathological factors. Within this cohort, 98 PCa deaths were confirmed over an average follow‐up period of 12.7 years after diagnosis. Variant allele carriers for three SNPs had significantly altered risk for PCSM [rs635261 at RNASEL, hazard ratio (HR), 0.35, 95% CI, 0.18–0.66; p = 0.002; rs915927 in XRCC1, HR, 1.91, 95% CI, 1.21–3.02; p = 0.009; and rs2494750 at AKT1, HR, 0.45, 95% CI, 0.23–0.90; p = 0.016). These results confirm the association of genetic variation in three genes with PCa lethality in a cohort of men with an inherited susceptibility to the disease and provide validation evidence that germline SNPs provide prognostic information for PCa patients. Development of a panel of germline biomarkers with clinical utility for distinguishing patients at detection who have an increased risk for fatal PCa is warranted. 相似文献
7.
2型糖尿病抵抗素基因单核苷酸多态性(SNPs)及胰岛素抵抗相关因素研究 总被引:1,自引:0,他引:1
目的:研究内蒙古地区汉族2型糖尿病人抵抗素基因5’端调节区单核苷酸多态性(SNPs)及胰岛素抵抗、血脂关系。方法:对81名2型糖尿病患者(分肥胖、非肥胖2组)及40名非糖尿病患者抵抗素基因测序分析,比较3组间SNPs及胰岛素敏感指数(ISI)、甘油三酯(TG)、总胆固醇(TC)、高密度脂蛋白(HDL—C)。结果:3组抵抗素基因5’端调节区等位基因频率比较显示组间无统计学差异。糖尿病肥胖组和非肥胖组胰岛素敏感指数(ISI)与对照组比较,差异有显著性(均为P〈0.01),糖尿病肥胖组和非肥胖组胰岛素敏感指数(ISI)比较差异也有显著性(P〈0.05),糖尿病肥胖组和非肥胖组甘油三酯均高于对照组(均为P〈0.01)。糖尿病肥胖组和非肥胖组之间比较,差异也有显著性(P〈0.05)。糖尿病肥胖组血HDL—C低于糖尿病非肥胖组和对照组,差异有显著性(分别为P〈0.05,P〈0.01),而糖尿病非肥胖组和对照组之间比较无统计学差异(P〉0.05),糖尿病非肥胖组和对照组之间比较无统计学差异(P〉0.05)。结论:内蒙古地区汉族2型糖尿病人与抵抗素基因5’端调节区单核苷酸多态性(SNPs)没有显著相关性。胰岛素抵抗与肥胖密切相关。2型糖尿病脂代谢紊乱是甘油三酯紊乱合并HDL—C紊乱,与肥胖密切相关。 相似文献
8.
目的:探讨ATP结合盒转运蛋白A3基因(ABCA3) rs13332514(C.1059G/A)、rs117515055(C.213C/T)两个多态性位点与陕西汉族人群新生儿呼吸窘迫综合征( NRDS)的遗传易感性。方法用SNaPshot多重微测序技术检测60例陕西汉族NRDS患者和120名健康对照者 ABCA3基因 rs13332514( C.1059G/A )、rs117515055( C.213C/T )两个多态性位点。结果rs117515055位点有两种基因型,对其进行比较,发现T等位基因在病例组(5.1%)高于对照组(3.1%),但是差异无统计学意义;rs13332514位点CC基因型频率及C等位基因频率在病例组高于对照组(50.8%vs44.1%,69.5%vs63.5%),差异亦无统计学意义。结论 rs117515055位点的T等位基因及rs13332514位点的C等位基因可能与汉族人群的NRDS有关,还需扩大样本量做进一步研究。 相似文献
9.
《Drug metabolism reviews》2012,44(1):169-184
Human N-acetyltransferase 1 (NAT1) alleles are characterized by one or more single nucleotide polymorphisms (SNPs) associated with rapid and slow acetylation phenotypes. NAT1 both activates and deactivates arylamine drugs and carcinogens, and NAT1 polymorphisms are associated with increased frequencies of many cancers and birth defects. The recently resolved human NAT1 crystal structure was used to evaluate SNPs resulting in the protein substitutions R64W, V149I, R187Q, M205V, S214A, D251V, E261K, and I263V. The analysis enhances knowledge of NAT1 structure-function relationships, important for understanding associations of NAT1 SNPs with genetic predisposition to cancer, birth defects, and other diseases. 相似文献
10.
G. Padma N. Swapna M. Mamata Bh. Charita T. Padma 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2014,36(8):579-585
Introduction: AGT gene harbors several variants of which 21 are found to be in high linkage disequilibrium as per Hapmap database. Studies delineating the importance of these tagged SNPs are very limited and lacking from Indian population. In the present study, we evaluated the contribution of four tagged SNPs namely, g.6635G?>?A, g.6506G?>?A, g.12840G?>?A, and g.13828T?>?C at AGT locus along with the analyses of haplotype and epistatic interactions in causing susceptibility to essential hypertension (EHT).Methods: About 215 hypertensives and 230 normotensives were genotyped for selected tagged SNPs using PCR-RFLP method.Results: Significant association was obtained for g.6635G?>?A and g.6506G?>?A polymorphisms wherein GG homozygotes for both the markers were at risk for developing the condition. g.13828T?>?C polymorphism specially, female heterozygotes (TC) were found to be at increased risk for EHT. Haplotype GGGC was found to have a significant protective effect (p?=?0.0059). Markers g.6506G?>?A and g.12840G?>?A resulted in the creation of new enhancer sites thereby affecting splicing process.Conclusion: The present report is the first one in the literature showing general- and gender-specific association of g.6506G?>?A and g.13828T?>?C polymorphisms, respectively, with EHT. However, further studies for replication of present observations are warranted from other populations and other parts of India. 相似文献