Huntington’s disease is a degenerative brain condition that impairs movement, affects cognitive function, and possibly induces behavioral and personality changes. Unfortunately, there is currently no cure for Huntington’s. But science may be one step closer, thanks to a new discovery by researchers from Cardiff University. Their study has made a breakthrough in understanding the mechanisms that influence the age of onset.
Huntington’s develops when an individual inherits one defective gene, HTT, whose mutation involves a DNA-segment referred to as CAG. In normal circumstances, the CAG segment appears several times in a row, repeating anywhere from 10 to 35 times. But when the HTT gene is defective, the sequence is mutated, because the CAG segment repeats more than 36 times—if it repeats at least 40 times, it will more than likely lead to the development of Huntington’s disease. The number of repetitions will also play a part in determining what age an individual would likely start developing symptoms of the condition.
For this study, researchers worked on comparing the age of Huntington’s onset with the DNA of over 6,000 patients with the disease. They discovered that the mechanism that controls the manufacturing and repairing of DNA can also influence the age of onset—the proteins involved in the repair process cause CAG segments to get longer, thereby reducing the likelihood and timeframe for developing Huntington’s disease.
Although these findings, published in the journal Cell, aren’t necessarily a cure for Huntington’s disease, the researchers believe they could be the gateway to potential breakthroughs for future treatments. They could also lead to discoveries for other diseases that develop as a result of inheriting a single gene.
Sources for Today’s Article:
Genetic Modifiers of Huntington’s Disease (GeM-HD) Consortium, “Identification of Genetic Factors that Modify Clinical Onset of Huntington’s Disease,” Cell 2015; 162(3): 516-526.
McIntosh, J., “Potential target for future Huntington’s disease treatment discovered,” Medical News Today web site, July 31, 2015; http://www.medicalnewstoday.com/articles/297489.php.