V-D-J deletion help - (Jan/19/2013 )

Hi I am an undergraduate student and would like some help in understanding the VDJ deletion.


The DNA encoding the Ig heavy chain isolated from a B lymphocyte synthesising an IgG2 antibody specific form diptheria toxin has the overall sequence:-

5'-V₁₇D₅J₂C_gamma2-C_gamma4-C_epsilon-3'
How many DNA deletions have taken place during the development of the B cell to obtain this sequence?

My lecturer explained that there are 3 deltions occuring, I didnt quiet understand why. Would someone mind explaining it to me?

Kushal on Sat Jan 19 21:36:53 2013 said:

Did you check the wiki on this?
http://en.wikipedia.org/wiki/V(D)J_recombination

Here you can cleary see the first 2 gene deletions.

The third one... well that is the one that happens at the end...
THe RNA has to be "taken care too" (if you see what I mean?) That primary RNA will also be cut and parts will also be deleted.