Fibroblasts used in this study included three WS patients-derived fibroblast lines (The genetic alterations detailed in Methods), AG03141 (homozygous 2476C > T mutation in the WRN gene), AG00780 (homozygous 1336C > T mutation in the RECQL2 gene), and AG06300 (with the polymorphism—a leucine for phenylalanine replacement at amino acid 1074 of the WRN protein). This evidence concerns the gene WRN and Werner syndrome.