IRP researchers link cases of ALS and FTD to a mutation associated with Huntington’s disease

Friday, December 4, 2020

Previously unknown genetic connection could be a target for gene therapy

A study led by researchers at the National Institutes of Health has made a surprising connection between frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), two disorders of the nervous system, and the genetic mutation normally understood to cause Huntington’s disease.

This large, international project, which included a collaboration between the National Institute of Neurological Disorders and Stroke (NINDS) and the National Institute on Aging (NIA), opens a potentially new avenue for diagnosing and treating some individuals with FTD or ALS.

Several neurological disorders have been linked to “repeat expansions,” a type of mutation that results in abnormal repetition of certain DNA building blocks. For example, Huntington’s disease occurs when a sequence of three DNA building blocks that make up the gene for a protein called huntingtin repeats many more times than normal. These repeats can be used to predict whether someone will develop the illness and even when their symptoms are likely to appear, because the more repeats in the gene, the earlier the onset of disease.

“It has been recognized for some time that repeat expansion mutations can give rise to neurological disorders,” said Sonja Scholz, M.D., Ph.D., investigator, NINDS Intramural Research Program. “But screening for these mutations throughout the entire genome has traditionally been cost-prohibitive and technically challenging.”