Also not having insurance doesn't mean instant death sentence. You can still pay yourself, however crazy amounts they are.
Disclaimer: I think whole US healthcare system is insane, especially the part where employers negotiate better rates. It's like socialised healthcare where higher earner pay more, but without any benefit to private companies...
That is illegal in the U.S., with the Genetic Information Nondiscrimination Act (GINA)
https://www.genome.gov/about-genomics/policy-issues/Genetic-...
>GINA prohibits health insurers from discrimination based on the genetic information of enrollees. Specifically, health insurers may not use genetic information to determine if someone is eligible for insurance or to make coverage, underwriting or premium-setting decisions. Furthermore, health insurers may not request or require individuals or their family members to undergo genetic testing or to provide genetic information.