Nonsense Mutation - Simple Example

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 Stop

Suppose 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 Stop

The 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:

    The way a child discovers the world constantly replicates the way science began. You start to notice what’s around you, and you get very curious about how things work. How things interrelate. It’s as simple as seeing a bug that intrigues you. You want to know where it goes at night; who its friends are; what it eats.
    David Cronenberg (b. 1943)

    The real drawback to “the simple life” is that it is not simple. If you are living it, you positively can do nothing else. There is not time.
    Katharine Fullerton Gerould (1879–1944)