Final answer:
Sequences 2, 3, and 4 show a chance of alteration in protein due to changes within the coding regions, while sequences 1, 5, and 6 have no alterations within coding regions and would not affect the resulting protein.
Step-by-step explanation:
The sequences provided can be classified based on their potential to modify the protein products they encode. This classification depends on whether the changes in nucleotide sequences occur in the protein coding regions (represented by plain letters) or the noncoding regions (represented by bold letters). Below is the classification according to the given sequences:
Chance of alteration in protein: Sequences 2, 3, and 4.
No alteration in protein: Sequences 1, 5, and 6.
Sequences 2, 3, and 4 have modifications within the protein coding regions, which could potentially alter the amino acid sequence of the protein product, and consequently its function, due to the central dogma of DNA-protein synthesis. On the other hand, sequences 1, 5, and 6 have not changed within the protein coding region and hence, would not alter the protein sequence or function.
DNA mutations and variations can dramatically change a protein's structure and function by altering the amino acid sequence. This can happen via translation of the mutated mRNA on ribosomes, which interprets the nucleotide sequence as instructions for protein synthesis. Each codon, a block of three nucleotides, corresponds to a specific amino acid or serves as a stop signal; hence, a mutation that changes a single nucleotide can either be silent, missense or nonsense, each affecting the protein in varying degrees.