What is the importance of SHM only occurring in B cells and

What is the importance of SHM only occurring in B cells and not in germ cells?

Solution

somatic hypermutation (SHM) is a mechanism which causes mutation in the variable region of B cells, it causes diversification in the B cell receptor so that the affinity of binding of variable region with the antigen is increased.Unlike germ line mutation it affects only individuals immune cells and doesn\'t passes to the offspring.These mutation mostly takes place at the hypervariable region of the DNA.