Ten to 15% of patients initially diagnosed with WS displayed mutations neither in WRN nor in LMNA. A subset of them presented with mandibular hypoplasia, deafness, and progeroid features (MDPL syndrome) and heterozygous mutations in the polymerase delta 1 (POLD1) gene (Weedon et al., 2013). The gene discussed is WRN; the disease is Werner syndrome.