LRP6 and obesity due to melanocortin 4 receptor deficiency: The homozygote LRP6 knockout is lethal for mice, whereas the heterozygote LRP6 knockdown mice are resistant to glucose intolerance and obesity on HFD; this is associated with the inhibition in the canonical Wnt pathway and resultant increase in mitochondrial biogenesis and reduce in endogenous hepatic glucose output.148