Research
Scientists learn why a sensitive part of our DNA is actually a built-in shield against the sun
Earth.com · By Eric Ralls ·
The Brief
- Early Earth had no ozone layer, so early life was exposed to intense ultraviolet light.
- Scientists were puzzled why DNA evolved to use thymine, a building block that takes significantly more UV damage than similar alternatives.
- The Earth.com article reports that researchers have explained why this sensitive DNA component works as a built-in shield against sunlight.
Why it matters
The finding offers a chemical explanation for why DNA uses thymine, which bears on how early life coped with UV exposure before the ozone layer formed.
Who’s affected
- biologists and researchers studying the origin of life and early evolution
- readers interested in DNA chemistry and UV damage
- #dna
- #thymine
- #uv radiation
- #evolution
- #origin of life
Before Earth had an ozone layer to block the sun, early life was constantly blasted by intense ultraviolet light. Because of this, scientists were puzzled by why DNA evolved using a chemical building block called thymine. It takes significantly more UV damage than similar…