The correlation is with the genes of what is known as the major histocompatibility complex (MHC). This region of the genome encodes part of the immune system.

Genes in the Major Histocompatibility Complex (MHC), which helps build the proteins involved in the body's immune response, also play a prominent role in odour through interaction with skin bacteria.

The major histocompatibility complex( MHC) is a group of closely-linked gene, Which code the major histocompatibility antigen and play a critical role in immune response in vertebrate animals.