Q23.1-2CC
Question
Of all the mutations that occur in a population, why do only a small fraction become widespread?
Step-by-Step Solution
VerifiedThe mutation that occurs in somatic cells is usually lost when the organism dies. However, the mutation that arises in gametes is transferred to the next generation within the population and becomes widespread.
The genes of the organism can be altered in many ways from the mutation. It modifies the functions of the essential proteins. The types of mutations include base substitutions, deletions, and insertions.
Base pair substitutions: When the mutation occurs in single base pairs, it is called a point mutation. Point mutation is classified as silent, nonsense, and missense mutation.
Deletion and insertion: Deletion mutation occurs when base pairs are lost from the DNA sequence. Attachment of additional base pairs is called insertion.
Errors in DNA replication and recombination, chemical damage, radiation, improper repair mechanisms, mismatch repair, and direct repair of damaged DNA lead to a mutation in organisms.
For example, the incorporation of DNA polymerase into non-complementary base pairs can lead to an error in DNA replication. The misincorporated base pair would lead to mutation.
The mutation that spreads among the population through gametes is called a germline mutation. In contrast, somatic mutation, which occurs in a body cell, is not passed down. In humans, cystic fibrosis, hemophilia, and cystic fibrosis are hereditary diseases caused by mutation.
The sporadic or spontaneous mutation that occurs in body cells leads to various cancer. They affect a few cells in the body and do not transform to the next generation.
Thus, a mutation that occurs in germline cells that are fewer or smaller fractions compared to body cells is transferred through gametes to the next generation. Therefore, certain mutations can be widespread in the population.