Table of Contents
How do mutations affect protein structure?
Generally, mutations result in reduced protein function or no protein function. A mutation with reduced function is called a leaky mutation because some of the wild-type function “leaks” through into the phenotype. A mutation that results in no protein function is called a null mutation.
What are three different examples of mutations that can affect protein synthesis?
There are three types of DNA Mutations: base substitutions, deletions and insertions.
- Base Substitutions. Single base substitutions are called point mutations, recall the point mutation Glu —–> Val which causes sickle-cell disease.
- Deletions.
- Insertions.
How do mutations cause changes in the structure and function of a protein?
Mutations can lead to changes in the structure of an encoded protein or to a decrease or complete loss in its expression. Because a change in the DNA sequence affects all copies of the encoded protein, mutations can be particularly damaging to a cell or organism.
What type of mutation will not affect the protein produced?
Silent Mutation: Although a change in the DNA sequence occurs, this type of mutation does not change the protein that is to be produced. This is because multiple genetic codons can encode for the same amino acid.
Do mutations always affect the resulting protein?
No; only a small percentage of mutations cause genetic disorders-most have no impact on health or development. For example, some mutations alter a gene’s DNA sequence but do not change the function of the protein made by the gene. Often, gene mutations that could cause a genetic disorder are repaired by certain enzymes before the gene is expressed and an altered protein is produced.
What effect can a mutation have on a protein?
A mutation in DNA alters the mRNA, which in turn can alter the amino acid chain. A base substitution may have three different effects on an organism’s protein. It can cause a missense mutation, which switches one amino acid in the chain for another.
What does mutation have no effect on a protein?
Because of this, a single change in the DNA sequence could result to various changes in the protein level: Silent mutation is when a mutation occurs but it has no effect on the protein. Missense mutation on the other hand is when the substitution results to a different amino acid — e.g. from UUU a mutation occurs and gives UUA.