Similar to Ai-DKO mice, Ai-IRKO mice also showed adipose tissue regeneration from lipodystrophy after withdrawal of tamoxifen15, and, like the Ai-DKO mice, also showed a 1.4- to 1.6-fold increase in serum SerpinA1 levels 3 days after tamoxifen injection (Fig. 1c). This evidence concerns the gene SERPINA1 and lipodystrophy.