transition mutations

Transition mutations are a type of point mutation in genetics where a single base pair in DNA is altered. These mutations occur when a pyrimidine base (thymine or cytosine) is substituted for another pyrimidine, or when a purine base (adenine or guanine) is substituted for another purine. For example, a GC base pair might replace an AT base pair.1

These changes can affect protein synthesis during translation. If a transition mutation results in a codon that codes for a different amino acid with different properties, it's called a missense mutation, potentially altering or losing protein function. A more severe outcome is a nonsense mutation, which introduces a premature stop codon, halting protein synthesis and likely causing complete loss of function. Transition mutations are often caused by errors during DNA replication or by external factors like radiation.1