https://www.nytimes.com/2020/03/09/...atient-castillejo.html?searchResultPosition=2 If there was a genotype that was resistant to MECFS, then perhaps we could undergo bone marrow transplants like this guy.
In the case of ME/CFS I can't think how it could ever be discovered if there is a resistant genotype, we can't look at people who have been exposed to ME/CFS to see if they caught it or not.