Which type of mutation could lead to a premature stop codon in protein synthesis?

A premature stop codon can occur through various types of mutations that affect the genetic code.

Substitution mutations involve the alteration of a single nucleotide in the DNA sequence. If this change occurs in a manner that converts a codon into a stop codon (UAA, UAG, or UGA), it would prematurely halt the translation process, leading to a truncated protein.

Insertion mutations involve the addition of one or more nucleotides into the DNA sequence. Depending on where this additional nucleotide is inserted, it can cause a shift in the reading frame of the codons, which may ultimately lead to the formation of a stop codon earlier than intended.

Deletion mutations entail the removal of nucleotides from the DNA sequence. Similar to insertions, deletions can also result in a frameshift, potentially altering the codon sequence to include a stop codon prematurely.

Thus, the possibility of a premature stop codon arises with all these mutations, making the answer comprehensive in recognizing the impact of different mutation types on protein synthesis.