A new syndrome, a new role for a gene

An international team led by Richard P. Lifton, M.D., Ph.D., chair and Sterling Professor of Genetics, and Ute I. Scholl, M.D., a postdoctoral associate in Lifton’s lab, has implicated a gene known as KCNJ10 in a previously unreported medical syndrome.

Mutations in KCNJ10, which codes for an ion channel that is expressed in the brain, kidney, and inner ear, cause seizures and deafness in mice. In the April 7 issue of Proceedings of the National Academy of Sciences, Scholl and colleagues report KCNJ10 mutations in five patients from four families with a syndrome that features—in addition to complex neurological problems—a defect in the kidney’s ability to manage potassium and magnesium levels.

These electrolyte abnormalities are attributed to a loss of the ion channel’s contribution to maintaining the activity of the kidney’s sodium-potassium pump.

The authors dubbed the disorder SeSAME syndrome because it features seizures, sensorineural deafness, ataxia, mental retardation and electrolyte imbalance.

“A study like this would have taken years in the past,” says Lifton, a Howard Hughes Medical Institute investigator, but with new techniques, “it was accomplished in a few weeks by a single fellow in the lab.”