Question

How do mutations occur?

Answer 1

Hint: A mutation is a heritable change in a DNA sequence. Mutations can be a consequence of DNA copying mistakes that occur during cell division, exposure to ionizing radiation, exposure to chemicals that are known as mutagens, or infection by viruses. Germ line mutations happen in the eggs and sperms and can be inherited to offspring, while somatic mutations happen in body cells and are not passed on.

Complete answer:
A gene variant is a permanent difference in the DNA sequence that makes a gene. This type of genetic change was known as a gene mutation, but as we know that changes in DNA do not always cause disease, it is now referred to as gene variant. Variants can affect one or more DNA building blocks i.e., nucleotides in a gene.
The smallest mutations are known as point mutations, in which only an individual base pair is changed into some other base pair. This another type of mutation is not similar to mutation, in which an amino acid sequence is changed. Such mutations lead to either the production of a different protein or the premature termination of a protein.
As opposed to nonsynonymous mutations, synonymous or similar mutations do not change an amino acid sequence, although they are present only in sequences that code for amino acids. Synonymous mutations occur because many amino acids are encoded by multiple codons. Depending on their function, silent mutations can be either truly silent or extraordinarily essential.
Mutations may also be of other types like in the form of insertions or deletions. They can have a broad variety of lengths.

Note:
Gene variants can be passed onto offspring from a parent or occur during a person’s lifetime:
Inherited (or hereditary) variants are passed from parent to child and are present throughout a person’s life in almost each and every cell in the body. These variants are also called germline variants. Non-inherited variants are present at some time during a person’s life and are present only in certain cells, not in every cell in the body.