HCP5
From Infogalactic: the planetary knowledge core
The gene known as HCP5 (HLA Complex P5) is a human endogenous retrovirus, meaning that it is a fossil of an ancient virus that at one time infected people, but has now become an integral part of the human genome.[1]
One variation of HCP5 appears to provide some delay or resistance to the development of AIDS when a person is infected with HIV. This variation of HCP5 frequently occurs in conjunction with a particular version of an immune system gene called HLA-B.[1]