A gene that causes Alzheimer's drugs to fail

by Darwin Melicdem for Medical Daily:Alzheimer’s disease is one of the leading causes of death in the U.S. Despite the growing number of patients there are still no cure available, making it the only disease that cannot be treated among the top causes of deaths in the country.Healthcare providers currently focus on maintaining mental function, managing behavioral symptoms and slowing down the effects of Alzheimer’s to help patients. Scientists to date continue to face challenges in creating an effective cure for Alzheimer’s.But a recent study offers new information about how treatments have been failing to stop the disease. Researchers found that there is a specific gene that blocks treatments in some patients but not in other people, Medical News Today reported Monday.The gene, called CHRFAM7A or fusion gene, is only present in 75 percent of people. It fuses a gene that encodes a receptor for the neurotransmitter acetylcholine and an enzyme known as kinase.Acetylcholine supports memory and learning. However, the fusion gene is only found in humans.That means treatments of Alzheimer’s will appear effective in tests with animal subjects and in the lab but not in human subjects.“Since this human fusion gene was not present in the animal models and screening systems used to identify drugs, 75 percent of Alzheimer's patients who do carry this gene are less likely to benefit and therefore are at a disadvantage,” Kinga Szigeti, study lead and director of the Alzheimer's Disease and Memory Disorders Center at the University at Buffalo in New York, said."This may account for the translational gap," she added.How The Alzheimer's Drugs WorkAbout three out of four available Alzheimer's drugs are designed to target the acetylcholine receptors, Szigeti said. While some treatments focus on the alpha-7 acetylcholine receptor.For the study, Szigeti’s team analyzed certain inhibitors in patients with the CHRFAM7A gene and those without. The researchers gathered data of 345 people with Alzheimer's from a 10-year study by the Texas Alzheimer's Research and Care Consortium.The team found that modifying treatments for Alpha 7 receptor could better treat Alzheimer's disease. However, the drugs work on certain people.The researchers called for a more personalized approach to drug testing and development based on the presence of the fusion gene. Their findings indicate that one drug may work for 25 percent of Alzheimer's patients while 75 percent of people may see it ineffective.Estimates show that there are over five million people currently living with Alzheimer’s disease in the U.S. Public health officials expect the figure to grow to 16 million Americans by 2050.Source