Question

Receptor editing affects:

a) only light chain genes
b) both heavy and light chain genes
c) only heavy chain genes
d) the mRNA transcripts of immunoglobulin genes, not the genes themselves

Answer 1

Receptor editing affects both heavy and light chain genes, and results in each antibody having a unique variable region capable of binding a different antigen.

Step-by-step explanation:

Receptor editing affects both heavy and light chain genes (b). In germ-line B cells, an enzyme called DNA recombinase randomly excises V and J segments from the light chain gene. Splicing at the mRNA level results in further gene rearrangement, resulting in each antibody having a unique variable region capable of binding a different antigen.