When exposed to excessive amounts of UVB radiation, the Thymines get substituted out for Cytosines! And now, there is a defect in the DNA which, if it doesn't get repaired in a timely manner, will lead to the effects we all have experienced as sunburn: burning, red skin, pain, and sometimes, blistering.
To eventually get back to the topic of how disarming this normal (and actually healthy) repair process is linked to a possible treatment for eczema and other skin disorders, we have to skip to another fave topic of mine, the inflammatory response. I'll make the link more explicit in a future post coming soon. But for the next post, I'll continue on with DNA repair!