Simple Example
DNA: 5' - ATG ACT CAC CGA GCG CGA AGC TGA - 3' 3' - TAC TGA GTG GCT CGC GCT TCG ACT - 5' mRNA: 5' - AUG ACU CAC CGA GCG CGA AGC UGA - 3' Protein: Met Thr His Arg Ala Arg Ser StopSuppose that a nonsense mutation was introduced at the fourth triplet in the DNA sequence (CGA) causing the cytosine to be replaced with thymine, yielding TGA in the DNA sequence. Since TGA is transcribed-then-translated as UGA, the resulting transcript and protein product would be:
DNA: 5' - ATG ACT CAC TGA GCG CGA AGC TGA - 3' 3' - TAC TGA GTG ACT CGC GCT TCG ACT - 5' mRNA: 5' - AUG ACU CAC UGA GCG CGU AGC UGA - 3' Protein: Met Thr His StopThe remaining codons of the mRNA are not translated into amino proteins because the stop codon is prematurely reached during translation. This can yield a truncated abbreviated protein product, which quite often lacks the functionality of the normal, non-mutant protein.
Read more about this topic: Nonsense Mutation
Famous quotes containing the word simple:
“All propaganda or popularization involves a putting of the complex into the simple, but such a move is instantly deconstructive. For if the complex can be put into the simple, then it cannot be as complex as it seemed in the first place; and if the simple can be an adequate medium of such complexity, then it cannot after all be as simple as all that.”
—Terry Eagleton (b. 1943)
“Each man’s private conscience ought to be a nice little self-registering thermometer: he ought to carry his moral code incorruptibly and explicitly within himself, and not care what the world thinks. The mass of human beings, however, are not made that way; and many people have been saved from crime or sin by the simple dislike of doing things they would not like to confess ...”
—Katharine Fullerton Gerould (1879–1944)