[Campbell Biology P.501] Short tandem repeats STRs are a type of simple sequence DNA. Which ... | Practice Question

Short tandem repeats STRs are a type of simple sequence DNA. Which statement accurately describes STRs or their analysis?

  • A: The repeated unit in an STR typically consists of more than 5 nucleotides.
  • B: STR analysis is primarily used to determine the exact number of repeats, which is constant across all individuals.
  • C: Simple sequence DNA, including STRs, makes up a significant portion (3%) of the human genome and is found at telomeres and centromeres.
  • D: The presence of STRs makes whole-genome sequencing easier due to their uniform nature.

Explanation

Option C is correct as the text mentions simple sequence DNA makes up 3% of the human genome and is located at telomeres and centromeres. Option A is incorrect because STR repeated units are 2-5 nucleotides, not more than 5. Option B is incorrect because repeat numbers vary among individuals. Option D is incorrect as STRs hinder, rather than facilitate, whole-genome sequencing due to reassembly difficulties.