GADD45B and obesity due to melanocortin 4 receptor deficiency: While there were no substantial effects of GADD45β loss on biometric parameters (Fig EV3I–K), similar to the whole‐body KO study (Fig 3), hepatocyte‐specific GADD45β silencing worsened the progression of insulin resistance upon high‐fat diet‐induced obesity (Fig 4I–K).