Read Codons, Reading Frames and Shared Meaning
The code is read as triplets; small indels shift the frame, while whole codon indels preserve downstream grouping.
Genetic Code is the central idea in this question pattern. Identify the condition in the stem before applying the method below.
Track the reading frame
Translation reads successive three-base codons. A one-base deletion changes every downstream codon until a stop; deleting three bases removes one codon but preserves the frame. Compare original and mutant codons position by position to count changed amino acids.
Use the code across species
The genetic code is nearly universal, allowing a human coding sequence to be translated in bacteria, with a few known exceptions such as some organellar codes.
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- ✓Codons are triplets.
- ✓Indels not divisible by 3 cause a frameshift.
- ✓The genetic code is nearly universal.
A frameshift can alter the sequence after the mutation even when the first amino acid stays the same.
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