[Campbell Biology P.494] A researcher identifies a new gene in a muskmelon and wants to infe... | Practice Question

A researcher identifies a new gene in a muskmelon and wants to infer its potential function. Based on the principles described in the text, which approach would be most effective for this inference and why?

  • A: Comparing the muskmelon's DNA sequence directly with DNA sequences of known genes from other plants because DNA is the fundamental genetic material.
  • B: Comparing the muskmelon's predicted amino acid sequence with protein sequences of known genes from other organisms, as protein sequence similarity better reflects functional conservation despite genetic code redundancy.
  • C: Analyzing the muskmelon's phenotype after gene knockout to deduce its function, as this is the most direct way to observe gene impact.
  • D: Searching for expressed sequence tags (ESTs) that match the new gene's sequence to confirm its transcription.

Explanation

The text highlights that 'Due to redundancy in the genetic code, the DNA sequence itself may vary more among species than the protein sequence does. Thus, scientists interested in proteins often compare the predicted amino acid sequence of a protein to that of other proteins.' This implies that comparing protein sequences is more effective for inferring function based on evolutionary conservation than comparing DNA sequences.