At the same time, we tested the hypothesis that RD is the most severe premature aging syndrome due to its high expression of progerin or farnesylated lamin A. Our protein quantification experiments suggested that embryonic expression of the LMNA c.1824C>T mutation causes an overexpression of lamin A, progerin, and prelamin A in skin from E17.5 (Fig. 1). The gene discussed is LMNA; the disease is premature aging syndrome.