Final answer:
Somatic hypermutation is a process that introduces random mutations in the genes encoding the variable regions of B cell receptors or antibodies, leading to the generation of antibody variants with different binding affinities for antigens.
Step-by-step explanation:
The changes in Ig genes during a B cell's life are primarily driven by a process called somatic hypermutation.
Somatic hypermutation is a mechanism that introduces random mutations in the genes encoding the variable regions of the B cell receptors (BCRs) or antibodies. These mutations result in changes in the amino acid sequence of the variable region, leading to the generation of antibody variants with different binding affinities for antigens.
Somatic hypermutation occurs in the germinal centers of secondary lymphoid organs and is essential for generating a diverse repertoire of antibodies that can effectively recognize and bind a wide range of antigens.