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Old 01-12-2012
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Immunology How many idiotype possibilities!

A germline B lymphocyte possesses 200 distinct V region genes, 5 J region genes, and 2 isotypic possibilities to rearrange for its selection of light chain synthesis. Assuming no recombinational inaccuracies, how many distinct idiotypes could be produced by combining this coding sequence with one heavy chain ?

A) 10
B) 205
C) 400
D) 1000
E) 2000
F) 4000
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Old 01-12-2012
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D?
ugh i hate immuno so much, totally forgot how to do this stuff "-_-
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Old 01-12-2012
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I guess D........ i dont remem immuno much.....ahhhhh
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Old 01-13-2012
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Arrow Answer is D

The correct answer is D) 1000

The light chain uses VJ combination .. so you would multiply V x J which gives you (200 x 5) = 1000

And that's it .. For idiotypes you don't need to take isotypes in consideration!
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The above post was thanked by:
drortho (01-15-2012), Hitman (01-13-2012), step_enhancer (01-14-2012)



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