Question from alternative source
Numerous mutation types can arise in the body. Cystic fibrosis is a genetic condition attributed to various mutations in the CFTR gene. A specific mutation in the CFTR gene related to cystic fibrosis results in an earlier-than-expected termination of translation in the gene sequence. Which kind of mutation leads to this translation error resulting in cystic fibrosis?
- silent
- missense
- nonsense
- deletion
Answer:
Nonsense
Explanation:
Nonsense mutations refer to those that create a premature stop codon. The stop codons include UAG, UAA, and UGA. This situation could occur if a nucleotide substitution happens in the mRNA codon UAC (which codes for the amino acid Tyrosine) changing to UAG (which signifies a stop codon).
Upon reaching this codon, the translation machinery would interpret it as a directive to end translation. Consequently, the mRNA would be released, leading to a truncated version of the amino acid, which is likely not functional and could be flagged for destruction by the cell.