Endogenous Retroviruses as Biochemical Evidence

Question 1

What are endogenous retroviruses (ERVs)?

Answer 1

A retrovirus that has become part of an organism’s genome and exists in every single cell of the body. They are long stretches of non-functional DNA.

Question 2

How do retroviruses become a part of the genome?

Answer 2

Retroviruses store their genetic information as RNA. The RNA genome is copied into DNA through reverse transcription. The DNA is then inserted into one of the host cells chromosomes.

Question 3

How does a retrovirus become ‘endogenous’?

Answer 3

If it inserts into a cell whose chromosomes will be inherited by the next generation, an ovum or sperm cell. The offspring of the infected person will then have a copy of the ERV at the same location.

Question 4

What percentage of ERVs make up the human genome?

Answer 4

8%.

Question 5

How can ERVs be used as evidence?

Answer 5

Comparison of the amount and location of ERV of different species can provide evidence for common ancestors.