Klotho-KO models share common features with patients harboring loss-of-function mutations in the Klotho gene, such as hyperphosphatemia and hypercalcemia63,64, However, no Klotho mutations in humans were yet linked to growth retardation, infertility, lung defect, and skin atrophy, as was observed in Klotho KO models1,65,66. This evidence concerns the gene KL and skin atrophy.