If the DNA which codes for a protein contains an error, or mutation,
it might result in a three dimensional protein structure that has an incorrect
shape (e.g., normal hemoglobin vs. sickle cell hemoglobin).
There are various types of mutations, including insertions, deletions, and
translocations. As an example, take the sentence (which is made of three
letter words, similar to triplet codons):
The fat cat saw the red dog
If we insert the letter 'x' before the f, the sentence will no loner have
the same meaning. In fact, it will be unreadable:
The xfa tca tsa wth ere ddo g
A similar effect will happen if we delete the f:
The atc ats awt her edd og
or if we translocate the 'e' in 'The' with the 'f' in 'fat':
Thf eat cat saw the red dog
Another example of deletion...
The cystic fibrosis transmembrane conductance regulator (CFTR) gene contains 250,000 base pairs. In the majority of cystic fibrosis patients, three base pairs are missing. This leads to the loss of a single amino acid from the 1,480 residues in the protein...and this change ultimately kills a person. more...
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