HGPS is caused by a single point mutation in the lamin A (LMNA) gene, resulting in the generation of progerin, a truncated splicing mutant of lamin A. The level of progerin accumulates with ages and leads to various ageing-associated nuclear defects including disorganization of the nuclear lamina and loss of heterochromatin. The gene discussed is LMNA; the disease is Hutchinson-Gilford progeria syndrome.