TCF7L2 gene polymorphism as a risk for type 2 diabetes mellitus and diabetic microvascular complications

Molecular Biology Reports - Type 2 Diabetes Mellitus (T2DM) is a chronic metabolic condition with various genetics and environmental influences that affects the capacity of the body to produce or...     

黑柄炭角菌的单核苷酸多态性研究

以SNPs作为分子标记,对黑柄炭角菌的生活史和遗传多样性进行研究。基于黑柄炭角菌的基因组文库,在两个菌株（X-WC和X-LY）的34个片段（19,680bp）中共发现193个SNPs,SNP发生率为0.981%。193个SNPs位点都有两个可变的核苷酸,其中132个转换,61个颠换,转换与颠换比率为2.16。此外,对两个菌株序列进行比较,发现了41个插入/缺失位点。从34个片段中选择4个片段,分别比较菌株内的SNPs情况。X-WC的菌株内SNP发生率为每个核苷酸1.308%（30/2293）,X-LY的菌     

A meta-analysis on associations of FTO,MTHFR and TCF7L2 polymorphisms with polycystic ovary syndrome

BackgroundWe aimed to better clarify the relationship between FTO/MTHFR/TCF7L2 polymorphisms and PCOS in a larger combined population by performing a meta-analysis.MethodsEligible articles were retrieved from Pubmed, Embase, Web of Science and CNKI. Review Manager Version was used to perform statistical analyses.ResultsForty-six studies were included for this meta-analysis. FTO rs9939609 polymorphism was found to be significantly associated with PCOS under dominant, recessive, over-dominant and allele comparisons, MTHFR rs1801131 polymorphism was found to be significantly associated with PCOS under recessive and allele comparisons, and MTHFR rs1801133 polymorphism was also found to be significantly associated with PCOS under dominant, recessive and allele comparisons in general population. In subgroup analyses, we found that positive results were mainly driven by the Asians.ConclusionsCollectively, this meta-analysis proved that FTO rs9939609, MTHFR rs1801131 and MTHFR rs1801133 polymorphisms may serve as predisposing factors of PCOS, especially for Asians.     

染色质免疫沉淀技术分析HePG2细胞TCF7L2蛋白与IDE基因转录启动子的结合

TCF7L2是一种重要的转录因子,通过Wnt信号途径,调节葡萄糖代谢.胰岛素降解酶(IDE)是细胞水平催化胰岛素降解的最关键的酶,与2型糖尿病(T2DM)高血糖、胰岛素抵抗、高胰岛素血症密切相关.为了检测HePG2细胞内转录因子TCF7L2与IDE基因启动子区的结合情况,采用染色质免疫沉淀技术结合PCR技术检测IDE基因启动子序列.结果表明,在特异性TCF7L2抗体免疫沉淀的DNA片段中扩增出IDE基因启动子序列,因此证实在HePG2细胞内,TCF7L2蛋白可与IDE基因转录启动子的特异区域结合,进而可能参与IDE基因的表达调控.     

Single nucleotide polymorphisms in an STS region linked to the Ncc-tmp1A locus are informative for characterizing the differentiation of chromosome 1A in wheat

Homoeoalleles of Ncc confer nucleus-cytoplasm (NC) compatibility on NC hybrids of wheat with the D plasmon of Aegilops squarrosa. To dissect the chromosomal region containing Ncc, a RAPD marker linked to the Ncc-tmplA locus, which is located on chromosome 1A of T timopheevi, was sequenced and converted to a PCR-based sequence-tagged-site (STS) marker. Five single nucleotide polymorphisms (SNPs) between T timopheevi and T turgidum. were detected in a 509-bp genomic DNA fragment. Based on the SNPs, the STS alleles in 164 accessions from emmer wheat, timopheevi wheat and two einkorn wheats, T. urartu and T. boeoticum were surveyed by PCR-RFLP analysis. The sequence comparisons and PCR-RFLP analyses revealed nine alleles based on six SNPs. These SNPs were highly conserved within each group of wheat, and all groups could be distinguished by particular combinations of the SNPs. All accessions of T. urartu had one unique STS allele as compared with the others. Our results indicate that the SNPs in the STS marker linked to the Ncc-tmplA locus would be informative for studies of the differentiation of chromosome 1A in wheat.     

Single nucleotide polymorphisms in the Melanocortin 1 Receptor gene are linked with lightness of fibre colour in Peruvian Alpaca (Vicugna pacos)

Melanocortin 1 receptor (alpha melanocyte stimulating hormone receptor) (MC1R) is a gene‐controlling melanogenesis in mammals. However, it is not well characterized in alpacas and its association with colour is not known. The aim of this study was to look for polymorphisms in the MC1R gene in Peruvian Huacaya alpacas and to analyse the relationship between MC1R single nucleotide polymorphisms (SNPs) and the variations in the instrumental measurement of colour of alpaca fibre. Sixty alpaca fibre samples from black, brown, cream and white animals (15 for each colour) were used to extract DNA from hair bulbs. Colour was measured with a spectrophotometer to obtain quantitative values (CieL*a*b*). Sixteen samples, four of each colour group, were sequenced. Eighteen SNP mutations, 10 not previously described, were found in these 16 sequences. Three of them were chosen (c.82A>G, c.865C>T, c.901C>T) to analyse genotypes by PCR‐RFLP in the other 44 fibre samples and to determine the association of mutations with instrumental colour. These three polymorphisms showed association with fibre lightness (P < 0.05), although there was no correlation with colour groups.     

2型糖尿病候选基因TCF7L2的研究进展

自发现转录因子7类似物2(TCF7L2)基因多态性与成人2型糖尿病(T2D)相关以来,该结论在不同人种中得到广泛证实.研究认为它可能通过影响肠胰岛素轴Wnt信号传导通路的胰高血糖素样肽-1(GLP-1)的表达或通过在胰岛β细胞的表达,或参与胰岛素的合成、加工、分泌,影响胰岛素敏感性等方式导致糖尿病发生.本文对该基因目前的研究成果及趋势进行相关论述.     

Single nucleotide polymorphism markers linked to root elongation rate in sugar beet

The aim of this study was to identify single nucleotide polymorphism (SNP) markers genetically linked to root elongation rate (RER) in sugar beet (Beta vulgaris L.). A population of 244 F₃ individuals, obtained from the cross between lines L01 (a low RER) and L18 (a high RER), was phenotyped by measuring RER of 11-d-old seedlings grown in a hydroponic culture. Two DNA bulks of 50 F₃ individuals with extreme phenotypes were used for bulk segregant analysis by restriction-associated DNA sequencing. A total of 20 376 SNPs were identified. Single nucleotide polymorphisms were filtered to reduce the number of the false positive and mapped on candidate chromosomal regions of the B. vulgaris reference genome. One of the total of SNPs selected, SNP10139, was strongly linked to RER (P < 0.01). The pattern of association between the SNP10139 genotype and RER was also evaluated on a breeding line panel comprising 40 low and 40 high RER individuals with different allele frequencies between groups (P < 0.01). The SNP10139 sequence was mapped on the B. vulgaris peptide transporter (PTR) gene, a carrier that influences root elongation in Arabidopsis thaliana. Our results suggest that SNP10139 influence RER in sugar beet, and sequence information can be used in marker-assisted selection programs.     

Single nucleotide polymorphisms (SNPs) are inherited from parents and they measure heritable events

Single nucleotide polymorphisms (SNPs) are extensively used in case-control studies of practically all cancer types. They are used for the identification of inherited cancer susceptibility genes and those that may interact with environmental factors. However, being genetic markers, they are applicable only on heritable conditions, which is often a neglected fact. Based on the data in the nationwide Swedish Family-Cancer Database, we review familial risks for all main cancers and discuss the evidence for a heritable component in cancer. The available evidence is not conclusive but it is consistent in pointing to a minor heritable etiology in cancer, which will hamper the success of SNP-based association studies. Empirical familial risks should be used as guidance for the planning of SNP studies. We provide calculations for the assessment of familial risks for assumed allele frequencies and gene effects (odds ratios) for different modes of inheritance. Based on these data, we discuss the gene effects that could account for the unexplained proportion of familial breast and lung cancer. As a conclusion, we are concerned about the indiscriminate use of a genetic tool to cancers, which are mainly environmental in origin. We consider the likelihood of a successful application of SNPs in gene-environment studies small, unless established environmental risk factors are tested on proven candidate genes.     

ADIPOQ,KCNJ11 and TCF7L2 polymorphisms in type 2 diabetes in Kyrgyz population: A case‐control study

The aim of this study was to ascertain the polymorphic markers profile of ADIPOQ, KCNJ11 and TCF7L2 genes in Kyrgyz population and to analyze the association of polymorphic markers and combinations of ADIPOQ gene's G276T locus, KCNJ11 gene's Glu23Lys locus and TCF7L2 gene's VS3C>T locus with type two diabetes (T2D) in Kyrgyz population. In this case‐control study, 114 T2D patients 109 non‐diabetic participants were genotyped using polymerase chain reaction‐restriction fragment length polymorphism (PCR‐RFLP). Two individual polymorphisms (ADIPOQ rs1501299, KCNJ11 rs5219) were found to be associated with T2D. We found two (Lys23Lys/CC and Glu23Lys/CT) of the overall nine combinations, which were more prevalent in T2D group compared to controls (χ² = 4.21, P = 0.04). Lys23Lys/CC combination was associated with a 2.65‐fold increased likelihood of T2D (OR = 2.65, 95% CI 1.12‐6.28), whereas the Glu23Lys/CT combination also increased such likelihood (OR = 3.88, 95% CI 1.27‐11.91). This study demonstrated some association of 276T allele and ADIPOQ gene G276T heterozygous genotype as well as KCNJ11 gene 23Lys allele with T2D in ethnic Kyrgyz, but study results should be interpreted with caution because of the limited statistical power.