Question

The major histocompatibility complex (MHC) of genes consists of a linked set of genetic loci encoding many of the proteins involved in antigen presentation to T cells, most notably the MHC glycoproteins that present peptides to the T cell receptor. The outstanding feature of MHC genes is their extensive polymorphism. Most MHC alleles differ from one another by multiple amino acid substitutions, and these differences are focused on the peptide-binding site and adjacent regions that make direct contact with the T cell receptor. New MHC alleles can be created when DNA segments are exchanged between different chromosomes. What is this called?

Gene duplication
Recombination
Gene conversion
Antigenic shift
Antigenic drift

Answer 1

The process by which new MHC alleles are created through the exchange of DNA segments between different chromosomes is called recombination, contributing to the diversity and polymorphism of the MHC genes. Option b.

Step-by-step explanation:

The exchange of DNA segments between different chromosomes leading to the creation of new major histocompatibility complex (MHC) alleles is known as recombination. This process is fundamental to the diversity of MHC molecules, which are responsible for the presentation of antigens to T cells.

The extensive polymorphism seen in MHC genes, particularly at the peptide-binding site and adjacent regions that make contact with the T cell receptor, is largely due to recombination. In this context, recombination provides a genetic mechanism that enhances the immune system's ability to recognize and respond to a wide array of pathogens.

So Option B is correct.