After more than three decades of studying life-threatening sickle cell disease, the most prevalent of all hereditary illnesses, University of Michigan Medical School researchers have discovered that an anti-depressant marketed since the 1960s wipes out the disorder in lab-tested human blood and mice.

If upcoming clinical trials prove it’s safe for adult sickle cell patients to ingest tranylcypromine, the anti-depressant could be an alternative to the current treatment — hydroxyurea — which is mainly a cancer fighter.

Hydroxyurea, which also is highly toxic, is only moderately effective on about half of sickle cell sufferers, most of whom are of African descent. The disorder, which causes blood cells to harden, become C-shaped, and ultimately clog arteries, also strikes people of Mediterranean, Middle Eastern and South Asian ancestry.

The genetic mutation that causes sickle cell disease was the first mutation of any inherited disease to be discovered, a finding made in 1949, also at the University of Michigan. That was a “fascinating” discovery, said molecular biologist and chemist James Douglas Engel, lead researcher in Michigan’s current sickle cell study, published last month in Nature Medicine.

“It prompted me,” Engel continued, “to believe that, ‘okay, here’s a disease we’re really going to be able to [soon] cure.’ It was with that idea that I began this work 35 years ago … It wasn’t until about 10 years ago that we figured out what a possible mechanism for controlling [the defect] might be.”