Question

In human cells, there are approximately 45 V segments, 23 D segments, and 6 J segments in the Ig heavy chain gene region in the immunoglobulin (antibody) heavy chain gene locus before any gene rearrangements occur.

How many possible heavy chain proteins can be created from these different segments, simply due to combinatorial diversity?

Please enter an exact number.

Answer 1

Antibody divversity is increased by the random rearrangement of multiple germ-line gene segments.We can calculate the diversity by gene rearrangements. In human cells any of the 45 V gene segments can combine with any of the 23 D gene segments and any of the 6 J gene segments. This rearrangement can result in a considerable amount of heavy-chain gene diversity. This can be calculated by mutiplying all the three numbers as 45 23 6 = 6210. Thus, 6210 possible combinations can result due to combinatorial V-D-J joining.