The frequency of diabetes-associated TCF7L2 genotypes was greater in cases ascertained for positive family history and early onset (rs4606565, P = 0.02); the population-attributable risk, estimated from the least-selected cases, is approximately 16%.
Our data indicate for the first time that TCF7L2 gene variants confer an increased risk for early impairment of glucose metabolism in obese children, which is consistent with adult studies identifying TCF7L2 as a major diabetes susceptibility gene.
In the near future, large-scale genome-wide association studies will fully extend the genome coverage, potentially delivering other common diabetes-susceptibility genes like TCF7L2.
In this issue of the JCI, Lyssenko and colleagues report on their human and isolated islet studies and suggest that the risk allele increases TCF7L2 expression in the pancreatic beta cell, reducing insulin secretion and hence predisposing the individual to diabetes (see the related article beginning on page 2155).
Of 100K SNPs, one (rs7100927) was in moderate LD (r2 = 0.50) with TCF7L2 (rs7903146), and was associated with risk of diabetes (Cox p-value 0.007, additive hazard ratio for diabetes = 1.56) and with tFPG (GEE p-value 0.03).
We genotyped four single nucleotide polymorphisms (SNPs) of TCF7L2 (rs7901695, rs7903146, rs11196205 and rs12255372) in 831 subjects with diabetes and 437 control subjects.
In addition to its recently recognized role in diabetes, aberrant TCF7L2 expression has been implicated in cancer through regulation of cell proliferation and apoptosis by c-MYC and cyclin D. It has been hypothesized that germline variants within the TCF7L2 gene previously associated with diabetes may affect cancer risk through the Wnt/beta-catenin signaling pathway.
LADA shares genetic features with both type 1 (HLA, INS VNTR, and PTPN22) and type 2 (TCF7L2) diabetes, which justifies considering LADA as an admixture of the two major types of diabetes.
Polymorphisms of the transcription factor 7-like 2 (TCF7L2) gene have been associated with insulin sensitivity and diabetes, and the TCF7L2 gene is involved in the Wnt/beta-catenin signaling pathway, all factors thought to be important in the etiology of colon cancer.
In conclusion, several population-based samples suggest that variants in the TCF7L2 gene are associated with reduced kidney function or CKD progression, overall and specifically among participants without diabetes.
We analysed the recently reported type 2 diabetes (T2D) associated polymorphisms in the TCF7L2 gene using a case-control approach, under the hypothesis that TCF7L2 variants should show similar association if diabetes in FCPD is similar to T2D.
Our study provides the first significant evidence of association between the TCF7L2rs7903146 polymorphism and type 2 diabetes risk in a large African American population and also demonstrates that the diabetes risk conveyed by the rs7903146 risk allele is substantially increased in the context of some metabolic risk factors for type 2 diabetes.
TCF7L2 type 2 diabetes susceptibility alleles are associated with islet autoantibody-negative but not autoantibody-positive new onset diabetes in young patients.
In this study, we aimed to confirm the effect of the TCF7L2 polymorphism rs7903146 on diabetes risk in a Brazilian population and to assess the use of this genetic marker in improving diabetes risk prediction in the general population.
Recent human studies suggest transcription factor 7-like 2 (TCF7L2) polymorphism predisposes to diabetes through modulation of beta-cell function and modulates lipid levels in familial dyslipidemia.
The transcription factor 7-like 2 (TCF7L2) has been recently associated with diabetes risk, and it may exert its effect through metabolic syndrome (MetS)-related traits and be subjected to modification by environmental factors.