Transgenic mice expressing the HERV-K env gene suffered neurodegeneration and motor symptoms characteristic of ALS.AVINDRA NATHAn endogenous human retrovirus called HERV-K is expressed at higher levels in the brains of amyotrophic lateral sclerosis (ALS) patients than in those of controls, and the virus is toxic to human neurons in culture, according to a study published this week (September 30) in Science Translational Medicine. Researchers further showed that mice expressing the HERV-K envelope gene develop symptoms of ALS, suggesting that the retrovirus may play a causal role in neurodegeneration.
“The new study is substantial and impressive in that it has employed a wide range of powerful in vivo and in vitro molecular biological, immunological, genetic, and other techniques,” Jeremy Garson, a medical virologist at University College London who was not involved in the work, wrote in an email. “The new data presented in the paper represents a significant contribution to our understanding of the potential role of endogenous retroviruses in neurological disease.”
“It’s a very, very important paper,” said Mount Sinai’s Daniel MacGowan, who also did not participate in the research. But, he added, “it didn’t show the smoking gun [at the molecular level] so there’s still the possibility that it’s an epiphenomenon. . . . We need more brain samples.”
In 2006, neurovirologist ...