Mandibular hypoplasia, deafness, and progeroid features with lipodystrophy (MDPL; MIM #615381) syndrome is a recently discovered, exceedingly rare autosomal dominant disorder caused by mutations in the DNA polymerase delta 1, catalytic subunit gene (POLD1), encoding a catalytic subunit of the lagging strand DNA polymerase, resulting in genomic instability, and cellular senescence. Here, POLD1 is linked to mandibular hypoplasia-deafness-progeroid syndrome.