For years my thumbnail has had horizontal ridges and an extremely large bump about a 1/4 way along the nail from the cuticle. My dad told me it was genetic, but after seeing pictures of habit tic thumbs I am convinced it's the same.

For as long as I can remember, going on +18 years, I have always rubbed and bitten the cuticle. The only difference I can see from others, is the large bump. I was wondering if anyone has something similar? Mine seems like an extreme form of Habit tic, but maybe it's just because I've had it for so long? Many thanks.