Little is known about the pathophysiology of human senescence. Hutchinson-Gilford progeria syndrome (HGPS) is an exceedingly rare but typical progeria, clinically characterized by postnatal growth retardation, midface hypoplasia, micrognathia, premature atherosclerosis, absence of subcutaneous fat, alopecia, and generalized osteodysplasia with osteolysis and pathologic fractures. The median age at death is 13.4 years, usually due to coronary artery disease (1). Dominant inheritance is likely, recessive cases probably being the result of germinal mosaicism (1).

Lamin A/C proteins, encoded by the LMNA gene, are major, ubiquitous components of nuclear laminae (2). A wide spectrum of human disorders is ascribed to mutations at the LMNA locus (3). The mandibulo-acral dysplasia phenotype, resulting from a LMNA founder mutation, shares several features with HGPS, although life expectan-