A virus that has been in our DNA for millions of years may be resurfacing in the form of ALS, scientists reported Thursday.
The discovery may lead scientists to finding a treatment for the incurable disease.
The virus is called HERV-K, and it incorporated itself — permanently — into the human genome between 2 and 5 million years ago. It's a human endogenous retrovirus — an example of nature's own genetic engineering.
Because they're part of the DNA, they are passed down from generation to generation in the same way as genes for eye color or height. Experts estimate that these viruses make up as much as 8 percent of the human genome.