How do you get keloids?

Keloids are scar tissue....a wound will "heal" over and over again....and the keloid grows. I had them on my ears (from ear piercings)....a plastic surgeon can remove them...but sometimes they come back. You can get them from any type of skin injury (depending on how prone you are to them). I know people who got keloids from tattoos, and people that got them from just a cut on their skin.

isnt that when you come in contact with a nuclear area

Keloids are areas of scar tissue that have "gone wild" (become large, raised, and usually shiney white).
While the exact cause of the aberrant formation is not known, there seems to be a heredity factor

Keloids are basically scars that don't stop growing when they should. Infected wounds are more likely to result in excessive scarring but, other than that, there really aren't any ways to "get" them. Also, African-Americans and Asian people have a higher risk of forming keloids after injury but no one really knows why.