Answer to Question #165278 in Genetics for Sam

Question

Assess the possibility of errors occurring during the stages of protein synthesis, particularly during transcription and translation. Analyse the cause and effect of genetic mutations in DNA, including:

• Missense 

• Nonsense

• Silent

• Insertion

• Deletion

• Duplication

• frameshift

Provide examples of the impact that these errors may have on the end products of protein synthesis

Answer 1

Missense

Is a genetic alteration in which a single base pair substitution alters the genetic code in a way that produces an amino acid that is different from the usual amino acid at that position.

Nonsense

A nonsense mutation is a change in one DNA base pair. Instead of substituting one amino acid for another, however, the altered DNA sequence prematurely signals the cell to stop building a protein. This type of mutation results in a shortened protein that may function improperly or not at all.

Silent

Silent mutations are mutations in DNA that do not have an observable effect on the organism's phenotype. They are a specific type of neutral mutation. The phrase silent mutation is often used interchangeably with the phrase synonymous mutation; however, synonymous mutations are not always silent, nor vice versa.

Insertion

Insertion is a type of mutation involving the addition of genetic material. An insertion mutation can be small, involving a single extra DNA base pair, or large, involving a piece of a chromosome.

Deletion

Deletion is a type of mutation involving the loss of genetic material. It can be small, involving a single missing DNA base pair, or large, involving a piece of a chromosome.

Duplication

Duplication is a type of mutation that involves the production of one or more copies of a gene or region of a chromosome. Gene and chromosome duplications occur in all organisms, though they are especially prominent among plants. Gene duplication is an important mechanism by which evolution occurs.

Frameshift

A frameshift mutation is a genetic mutation caused by indels of a number of nucleotides in a DNA sequence that is not divisible by three. Due to the triplet nature of gene expression by codons, the insertion or deletion can change the reading frame, resulting in a completely different translation from the original.