Life Science and Medical News from Around the Globe
Dormant Ancient Genes May Awaken to Cause Deadly Disease–Human Endogenous Retrovirus-K (HERV-K) Genes May Be Involved in Amyotrophic Lateral Sclerosis (ALS) (Lou Gehrig’s Disease)
Scientists at the National Institutes of Health have discovered that reactivation of ancient viral genes embedded in the human genome may cause the destruction of neurons in some forms of amyotrophic lateral sclerosis (ALS). The results, published in the September 30, 2015 issue of Science Translational Medicine, suggest a link between human endogenous retroviral genes (HERVs) and ALS. The article is titled “Human Endogenous Retrovirus-K Induces Motor Neuron Disease.” The findings also raise the question of whether antiretroviral drugs, similar to those used for suppressing HIV, may help some ALS patients. For generations, humans have been passing on genetic remnants of HERV infections that may have happened millions of years ago. Although nearly eight percent of the normal human genome is made up of these genes, very little is known about their role in health and disease. “People call the genes for these viruses junk DNA. Our results suggest they may become activated during ALS,” said Avindra Nath, M.D., Clinical Director at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS) and a senior author of the study. “Ultimately we hope the results will lead to effective treatments for a heartbreaking disorder.” Currently, there is no effective treatment for the more than 12,000 Americans who live with ALS. This fatal disorder destroys neurons that control movements, including speaking, walking, breathing, and swallowing. On rare occasions, HIV-infected, AIDS patients develop ALS-like symptoms. In many of these patients, the symptoms can be reversed by treatment with antiretroviral drugs. Previous studies found reverse transcriptase, a protein encoded by retroviral genes, in the blood of some ALS patients, but its role in the disorder is unknown. These observations prompted Dr.