Quick Answer: Which DNA Mutation Is Most Damaging?

Are most DNA mutations harmful?

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..

Which type of mutation causes the least damage?

Point MutationsPoint Mutations A point mutation—the change of a single nitrogen base in a DNA sequence—is usually the least harmful type of DNA mutation. Codons are a sequence of three nitrogen bases in a row that are “read” by messenger RNA during transcription.

What disease is caused by deletion mutation?

Deletions are responsible for an array of genetic disorders, including some cases of male infertility, two thirds of cases of Duchenne muscular dystrophy, and two thirds of cases of cystic fibrosis (those caused by ΔF508).

What type of mutation is least likely to affect the protein?

The correct answer is (c) substitution. A substitution mutation occurs when one nucleotide is exchanged for another in the DNA sequence.

What are the causes of mutation?

These changes can be caused by environmental factors such as ultraviolet radiation from the sun, or can occur if an error is made as DNA copies itself during cell division. Acquired mutations in somatic cells (cells other than sperm and egg cells) cannot be passed to the next generation.

What are 3 examples of things in the environment that could cause mutations?

Environmental mutagens include : Radiations. Ionising radiations such as X rays, gamma rays, alpha particles, UV radiations and radioactive decay act as mutagens. Chemical.

What kind of mutation is the most dangerous?

Deletion mutations, on the other hand, are opposite types of point mutations. They involve the removal of a base pair. Both of these mutations lead to the creation of the most dangerous type of point mutations of them all: the frameshift mutation.

What type of mutation causes the most change?

Insertion or deletion of one or more nucleotides during replication can also lead to another type of mutation known as a frameshift mutation. The outcome of a frameshift mutation is complete alteration of the amino acid sequence of a protein.

Which mutation has greatest consequence?

Insertions and deletions are the mutations with the greatest consequence.

What are 3 causes of mutations?

Natural exposure of an organism to certain environmental factors, such as ultraviolet light and chemical carcinogens (e.g., aflatoxin B1), also can cause mutations. A common cause of spontaneous point mutations is the deamination of cytosine to uracil in the DNA double helix.

What are the 4 types of mutation?

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.

What mutations are not inherited?

Somatic mutation Somatic mutations are not inherited by an organism’s offspring because they do not affect the germline. However, they are passed down to all the progeny of a mutated cell within the same organism during mitosis. A major section of an organism therefore might carry the same mutation.

Which is worse insertion or deletion?

Insertion or deletion results in a frame-shift that changes the reading of subsequent codons and, therefore, alters the entire amino acid sequence that follows the mutation, insertions and deletions are usually more harmful than a substitution in which only a single amino acid is altered.

Which mutation will cause translation to stop?

Thus, nonsense mutations occur when a premature nonsense or stop codon is introduced in the DNA sequence. When the mutated sequence is translated into a protein, the resulting protein is incomplete and shorter than normal. Consequently, most nonsense mutations result in nonfunctional proteins.

Why are nonsense mutations harmful?

Direct damage to DNA or errors in the processes that generate messenger RNA (mRNA) from the DNA template can introduce mutations, with potentially harmful consequences. … Nonsense mutations introduce a stop codon ‘upstream’ of the correct signal so that translation is stopped early and a truncated protein is made.

What are the factors affecting mutation?

Both the nature of the gene and its environment can influence the mutation rate. The size of the gene, its base composition, its position in the genome, and whether or not it is being actively transcribed influence its mutation rate.

Can mutated genes be corrected?

Making such double-stranded breaks in DNA can result in unwanted genetic material being inserted or deleted, which can have consequences including activating genes that cause cancer. Most mutations cannot be corrected easily without creating these undesirable genetic by-products.

What are good mutations?

Beneficial Mutations Some mutations have a positive effect on the organism in which they occur. They are called beneficial mutations. They lead to new versions of proteins that help organisms adapt to changes in their environment. Beneficial mutations are essential for evolution to occur.