What role does TCF7L2 play in Haut?

TCF7L2 is a transcription factor central to Wnt signaling. In skin, TCF7L2 has been implicated in hair follicle cycling and wound healing, but evidence comes mainly from cell and animal models; direct human data on skin function are limited. TCF7L2 is best known for its strong association with type 2 diabetes risk (rs7903146). In skin, altered Wnt signaling via TCF7L2 variants could theoretically affect hair follicle development or epidermal regeneration, but clinically relevant effects are not well established. Consumer DNA tests reporting TCF7L2 variants should not be interpreted as skin predictors. The evidence is mechanistic and insufficient for actionable recommendations.