Cystic fibrosis

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Cystic fibrosis

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29 Posts

Malaysian
Forum Guru

Topics: 28
Posts: 778

05/01/04 - 12:29 PM

#26

if 1 codon isn't there then it should be in-frame mutation.That is exclusion of an amino acid reperesented by 3 codons(or repetitive of 3)whereas if it was not a rep. of 3 it would have led to a frame shift.Missense means that the normal amino acid has been replaced by another.

As most of u r quoting from all sort of sources that the mutation is due to absence of the 3 codons meant to code for phenylalanine(and not because of replacement of the phenylalanine by another amino acid)I strongly feel the answer is in-frame mutation.Unfortunately this answer sin't there??So the next best thing to choose is frame shift

Idiopathic
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Topics: 19
Posts: 641

05/01/04 - 12:39 PM

#27

Definitely not frameshift, not by the definition we have to go on.

BECAUSE the change involves one and only one amino acid, with the remainder of the peptide unaffected. That is, by definition, a missense mutation (even if it goes from an amino acid to no amino acid, as in this case).

Malaysian
Forum Guru

Topics: 28
Posts: 778

05/01/04 - 12:49 PM

#28

Can anyone give the definition of missense mutation?

Idiopathic
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Topics: 19
Posts: 641

05/01/04 - 01:15 PM

#29

A damaged DNA sequence whose products do not do what they are supposed to do. The sequence is meaningful, but its meaning is incorrect

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