Interestingly, leptin administration has been shown to favorably affect the metabolic profile, including dyslipidemia, hepatic steatosis, and insulin resistance, in both lipodystrophic patients (38–42) and mice (19, 43–47), suggesting that the therapeutic potential of AT in rescuing lipodystrophy-associated metabolic derangements may at least partially depend on proper leptin signaling. This evidence concerns the gene LEP and ataxia telangiectasia.