The transcription factor 7-like 2 gene and increased risk of type 2 diabetes: an update.
OBJECTIVE
The purpose of this review is to provide a comprehensive evaluation of the most important type 2 diabetes gene to date, transcription factor 7 like-2.


RESULTS
An important step to find genetic causes of type 2 diabetes in 2006 was the identification of the fact that variants in the gene encoding transcription factor 7 like-2 reproducibly increase susceptibility to type 2 diabetes in almost all populations studied. This gene has since then emerged as the most important type 2 diabetes gene. Genetic variants in transcription factor 7 like-2 confer a strong risk of type 2 diabetes possibly mediated by altering expression of transcription factor 7 like-2 in pancreatic islets. Risk variants in the transcription factor 7 like-2 influence insulin secretions both in vitro and in vivo. The risk T allele of this single nucleotide polymorphism also seems to have effects on the enteroinsular axis and the relationship between the incretin hormone glucose-dependent insulinotropic peptide and its target hormones, glucagon and insulin. Given transcription factor 7 like-2s' central role in the Wnt signaling pathway, it would be important to define whether the variant is associated with increased or decreased Wnt signaling.


CONCLUSIONS
The fact that transcription factor 7 like-2 is by far the strongest type 2 diabetes susceptibility gene to date emphasizes the importance of exploring the potential of manipulating this pathway in future treatment of the disease.
Lyssenko
Valeriya
V
Department of Clinical Sciences, Diabetes and Endocrinology, Lund University, Malmoe, Sweden. Valeri.Lyssenko@med.lu.se
D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology / Q000235:genetics* / Q000378:metabolism; D014644:Genetic Variation; D005947:Glucose / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism / Q000502:physiology*; D012307:Risk Factors; D012636:Secretory Rate / Q000502:physiology; D051820:TCF Transcription Factors / Q000235:genetics*; D058118:Transcription Factor 7-Like 2 Protein
D007328:Insulin; D051820:TCF Transcription Factors; C544894:TCF7L2 protein, human; D058118:Transcription Factor 7-Like 2 Protein; D005947:Glucose