Rsa digestion.

[Dr. Duncan Clark]

In article <397EA432.B37BE9C4 at pitt.edu>, Julia Liachenko <jul2 at pitt.edu>
writes
>Thank you for your help, I think I was not very clear.
>The defective allele contains an Rsa site, and heterozygotes are
>suppose to have 135bp and 108bp.
>But in homozygotes both alleles were defective, so I was expecting to
>see just 108 fragments.
>It looks like the digestion does not work for homozygotes even partially.
>Can you think of any reason for it?

Unless your homozygote samples are accidentally mixed i.e.

homozygote with no defective allele 135bp

homozygote with defective allele 108bp + 25bp

heterozygote 135bp + 108bp + 25bp

Or am I missing something?

Duncan

-- 
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sliced from time to time....

Duncan Clark
DNAmp Ltd.
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