Which type of mutation involves the substitution of one nucleotide for another?

Which type of mutation involves the substitution of one nucleotide for another?

• A. Frameshift mutation
• B. Point mutation
• C. Deletion mutation
• D. Duplication mutation

Answer: (B)

A point mutation is characterized by the substitution of one nucleotide for another in the DNA sequence. This can occur in several ways, such as transitions (where a purine is replaced by another purine or a pyrimidine by another pyrimidine) or transversions (where a purine is replaced by a pyrimidine or vice versa). Point mutations can have various effects on the protein produced, depending on the location of the mutation and whether it alters the amino acid sequence. It may lead to a silent mutation if the new codon still codes for the same amino acid, a missense mutation if it causes a change in a single amino acid, or a nonsense mutation if it creates a premature stop codon. In contrast, frameshift mutations involve the insertion or deletion of nucleotides, which alters the reading frame of the genetic code. Deletion mutations result in the loss of segments of DNA, and duplication mutations involve the repetition of sections of DNA. Understanding the nuances of these different types of mutations is essential in genetics, particularly in studying genetic diseases and evolution.

A point mutation is characterized by the substitution of one nucleotide for another in the DNA sequence. This can occur in several ways, such as transitions (where a purine is replaced by another purine or a pyrimidine by another pyrimidine) or transversions (where a purine is replaced by a pyrimidine or vice versa).

Point mutations can have various effects on the protein produced, depending on the location of the mutation and whether it alters the amino acid sequence. It may lead to a silent mutation if the new codon still codes for the same amino acid, a missense mutation if it causes a change in a single amino acid, or a nonsense mutation if it creates a premature stop codon.

In contrast, frameshift mutations involve the insertion or deletion of nucleotides, which alters the reading frame of the genetic code. Deletion mutations result in the loss of segments of DNA, and duplication mutations involve the repetition of sections of DNA. Understanding the nuances of these different types of mutations is essential in genetics, particularly in studying genetic diseases and evolution.