[Campbell Biology P.554] If the nucleotide variability of a specific gene locus in a populat... | Practice Question

If the nucleotide variability of a specific gene locus in a population is 0%, what can be inferred about the gene variability and the number of alleles at that locus?

  • A: Gene variability = 0%; number of alleles = 0
  • B: Gene variability = 0%; number of alleles = 1
  • C: Gene variability = 0%; number of alleles = 2
  • D: Gene variability > 0%; number of alleles = 2

Explanation

Nucleotide variability refers to variation at the DNA sequence level. If it's 0%, it means all individuals in the population have exactly the same DNA sequence at that locus. This implies there is only one type of allele for that gene, hence no gene variability either. So, gene variability is 0%, and the number of alleles is 1.