btw, if you were an evil empire and you wanted to get rid of the Hans...you could try to engineer a virus
https://pubmed.ncbi.nlm.nih.gov/23361009/
The SNP rs12252-C allele alters the function of interferon-induced transmembrane protein-3 increasing the disease severity of influenza virus infection in Caucasians, but the allele is rare. However, rs12252-C is much more common in Han Chinese.
you could try to make a bioweapon targeting IFITM3 that would then make you more prone to various virus.
They do it in gene therapy
https://research.hsr.it/en/news/a-new-ingredient-to-potentiate-gene-therapy.html
The researchers have found that cyclosporin H works by temporarily degrading IFITM3, a host cell protein involved in the defense against several viruses, without other immunosuppressive effects. Indeed, the levels of IFITM3 bounce back to normal around 6 hours after the treatment and without affecting the biological functions of these cells, a good starting point for its future clinical application.