The 2003 discovery of the HGPS gene, named lamin A (LMNA), laid the groundwork for the clinical trial. Indeed, in 2003, Dr. Collins was quoted as saying, "This genetic discovery represents the first piece in solving the tragic puzzle of Progeria. Without such information, we in the medical community were at loss about where to focus our efforts to help these children and their families. Now, we finally know where to begin."
They began by zeroing in on the LMNA gene and the HGPS genetic mutation, a single-letter "misspelling" in the LMNA gene located on chromosome 1. This gene carries the DNA recipe for lamin A, the protein glue that holds together the cell's nucleus. The mutated LMNA gene generates an abnormal Lamin A protein (also called progerin) that disrupts the cell's nuclear membrane. Because progerin wreaks havoc, cells become unstable and abnormal. The resulting gross disfigurement of the cell's nucleus is described as "blebbed," or lobular in shape.
(Recent research indicates that all people, not just children with HGPS, produce small amounts of progerin, and that this mutant protein may play roles in aging or longevity.)
Studying cells from HGPS patients, the NHGRI scientists found that the minute change in the LMNA gene's DNA sequence dramatically changed the way in which the sequence was spliced by the cell's protein-making machinery. The end result was the production of an abnormal lamin A protein that is missing a stretch of 50 amino acids near one of its ends.
Even before Dr. Collins and his research team tracked down the genetic mutation responsible for HGPS, Dr. Goldman had earned a stellar reputation for his cutting-edge basic research on the Lamin proteins in the cell nucleus.
Lamins were first described in the 1950s, and their protein structure was unraveled in the 1970s. The biochemistry of lami
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American Society for Cell Biology