Question

Why are developing B cells so much more likely to successfully recombine L chain genes than H chain genes?

Answer 1

Once a B cell can express m amd l chain on its membrane its officially a B cell.

RAG1, RAG2 and TdT are expressed only during the times, somatic recombination is occurring. Early, late pro and small pre B cell stages. TdT is turned off sooner than the recombinases, so that N nucleotide additions, to the gene segment join in L chains are not as common as in H chain sequences.

2 rounds of DNA recombination are required for, production of functional heavy and light chains. Both rounds depend on the joint action of recombination activation gene 1 and RAG 2 endonucleases with the DNA non homologous end joining pathway.

VDJ recombination that is variable diversity and joining. VDJ recombinases are involved.