Missing Fingernails
This genetic condition whereby you miss a fingernail or toenails is a genetic condition called anonychia, and it doesn't occur frequently. Most times the moon crest symbol beneath your fingernails goes missing.
Skin Writing
This is a common and not harmful genetic condition. It is called Dermatographism. People who have the condition develop welts or localized almost love-like reactions when they scratch on their skin. This condition can also happen when the skin is exposed to rubbing or pressure. The condition is also referred to as “skin writing.”