In an experiment to decipher the genetic code, a poly-AC mRNA (ACACACAC...) is synthesized. What pattern of amino acids would appear if this sequence were to be translated by a mechanism that reads the genetic code as
a quadruplet without overlaps?
Table of contents
- 1. Introduction to Genetics51m
- 2. Mendel's Laws of Inheritance3h 37m
- 3. Extensions to Mendelian Inheritance2h 41m
- 4. Genetic Mapping and Linkage2h 28m
- 5. Genetics of Bacteria and Viruses1h 21m
- 6. Chromosomal Variation1h 48m
- 7. DNA and Chromosome Structure56m
- 8. DNA Replication1h 10m
- 9. Mitosis and Meiosis1h 34m
- 10. Transcription1h 0m
- 11. Translation58m
- 12. Gene Regulation in Prokaryotes1h 19m
- 13. Gene Regulation in Eukaryotes44m
- 14. Genetic Control of Development44m
- 15. Genomes and Genomics1h 50m
- 16. Transposable Elements47m
- 17. Mutation, Repair, and Recombination1h 6m
- 18. Molecular Genetic Tools19m
- 19. Cancer Genetics29m
- 20. Quantitative Genetics1h 26m
- 21. Population Genetics50m
- 22. Evolutionary Genetics29m
11. Translation
The Genetic Code
Problem 21
Textbook Question
In an experiment to decipher the genetic code, a poly-AC mRNA (ACACACAC...) is synthesized. What pattern of amino acids would appear if this sequence were to be translated by a mechanism that reads the genetic code as
a doublet without overlaps?

1
Understand the problem: The poly-AC mRNA sequence alternates between adenine (A) and cytosine (C). The question asks us to determine the amino acid pattern if the genetic code is read as doublets (two nucleotides at a time) without overlaps.
Recall the concept of codon translation: Normally, the genetic code is read in triplets (three nucleotides at a time). However, in this problem, the mechanism reads doublets. Each doublet corresponds to a specific amino acid based on the experimental genetic code provided.
List all possible doublets from the poly-AC sequence: Since the sequence alternates as ACACAC..., the possible doublets are 'AC' and 'CA'. These doublets repeat throughout the sequence.
Determine the amino acids corresponding to the doublets: Using the experimental genetic code (which would need to be provided or referenced), identify the amino acids that correspond to 'AC' and 'CA'. For example, if 'AC' codes for amino acid X and 'CA' codes for amino acid Y, the pattern would alternate between X and Y.
Describe the resulting amino acid pattern: Based on the translation of the doublets, the amino acid sequence would alternate between the amino acids corresponding to 'AC' and 'CA'. This pattern would repeat throughout the length of the mRNA.

This video solution was recommended by our tutors as helpful for the problem above
Video duration:
3mPlay a video:
Was this helpful?
Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Genetic Code
The genetic code is a set of rules that defines how sequences of nucleotides in DNA and RNA are translated into amino acids, the building blocks of proteins. It consists of codons, which are triplets of nucleotides, each corresponding to a specific amino acid or a stop signal during protein synthesis.
Recommended video:
Guided course
The Genetic Code
Translation Mechanism
Translation is the process by which ribosomes synthesize proteins using mRNA as a template. In this context, the mechanism refers to how the ribosome reads the mRNA sequence to assemble amino acids into a polypeptide chain, which can occur in different reading frames depending on the codon structure.
Recommended video:
Guided course
Translation initiation
Doublet Reading
Doublet reading refers to interpreting the mRNA sequence in pairs of nucleotides instead of the standard triplet codons. This approach alters the way amino acids are assigned to the mRNA sequence, leading to a different pattern of amino acids being produced, as each pair of nucleotides corresponds to a specific amino acid.
Recommended video:
Guided course
Sequencing Overview
Related Videos
Related Practice
Textbook Question
456
views