Cells from donors with HGPS and WS also demonstrated lower levels of proliferation (80% and 71% lower for HGPS and WS, respectively; p = 0.0050 and p = 0.0082; Fig. 1E and F), whereas cells from the phenotypically less severe CS patient demonstrated no differences in proliferation compared to controls (p = 0.048; Fig. 1G). This evidence concerns the gene LMNA and Cowden syndrome 1.