Final answer:
The Class I loci found in humans are HLA-A, HLA-B, and HLA-C. These loci are part of the major histocompatibility complex (MHC) I genes and are responsible for encoding cell surface proteins that play a crucial role in the immune system. The high diversity of alleles at these loci leads to low chances of finding a complete genetic match between a donor and recipient.
Step-by-step explanation:
In humans, the Class I loci found are HLA-A, HLA-B, and HLA-C. These loci belong to the major histocompatibility complex (MHC) I genes, which play a crucial role in the immune system. MHC I loci are responsible for encoding cell surface proteins that help the immune system recognize self and non-self antigens.
Each of these Class I loci has many alleles that segregate in the population, resulting in high MHC polymorphism. Due to the high diversity of alleles, the odds of finding a complete genetic match between a randomly chosen donor and recipient's MHC genes are extremely low.
It is important to note that MHC I genes are found on the surface of all nucleated body cells, contributing to immune surveillance and allowing immune cells to detect infected or cancerous cells.