While searching for the genetic cause of and a treatment for Marfan syndrome, researchers have possibly found a way to help other patients with enlarged aortas as well, writes Gina Kolata at the New York Times.
People with Marfan syndrome typically are thin with long limbs and flexible joints. They also develop heart problems as the aorta grows.
As Kolata reports, Hal Dietz at Johns Hopkins University has been studying the genetic roots of the disease since the 1980s. In the 1990s, he and his colleagues homed in on variants in the fibrillin-1 gene, which encodes a protein important for connective tissue. This indicated that Marfan syndrome arose because "the tissue was falling apart because its molecular rivets did not work," Kolata says.
Dietz began to suspect that there was another factor at play, and TGF-β caught his attention. It needs the fibrillin-1 protein to attach to the connective tissue, and without it, TGF-β built up in the blood.
"That," Dietz tells the Times, "was one of the few 'aha' moments in my life."
He also found that the blood pressure drug losartan appeared, in mice, to block the effects of that TGF-β accumulation. That drug is currently part of a clinical trial to examine its effects on people with Marfan syndrome, Kolata says.
If it works, it could also help people without Marfan syndrome who have enlarged and torn aortas. Those patients appear to have higher levels of fibrillin-1 in the blood, a finding that is also undergoing validation.