Columbia University Medical Center (CUMC) researchers have discovered that a deficiency of the enzyme prohormone covertase (PC1) in the brain is linked to most of the neuro-hormonal abnormalities in Prader-Willi syndrome, a genetic condition that causes extreme hunger and severe obesity beginning in childhood. The discovery provides insight into the molecular mechanisms underlying the syndrome and highlights a novel target for drug therapy. The findings were published online on December 12, 2016 in the Journal of Clinical Investigation. The study is titled, "Deficiency in Prohormone Convertase PC1 Impairs Prohormone Processing in Prader-Willi Syndrome." "While we've known for some time which genes are implicated in Prader-Willi syndrome, it has not been clear how those mutations actually trigger the disease," said lead author Lisa C. Burnett, Ph.D., a post-doctoral research scientist in pediatrics at CUMC. "Now that we have found a key link between these mutations and the syndrome's major hormonal features, we can begin to search for new, more precisely targeted therapies." An estimated one in 15,000 people have Prader-Willi syndrome (PWS). The syndrome is caused by abnormalities in a small region of chromosome 15, which leads to dysfunction in the hypothalamus--which contains cells that regulate hunger and satiety--and other regions of the brain. A defining characteristic of PWS is insatiable hunger. People with PWS typically have extreme obesity, reduced growth hormone and insulin levels, excessive levels of ghrelin (a hormone that triggers hunger), and developmental disabilities. There is no cure and few effective treatments for PWS. Dr.Login Or Register To Read Full Story