My oldest daughter came home from school one day and asked me if I had a hitchhiker’s thumb. I had no idea what she was talking about. She proceeded to explain that hitchhiker’s thumb was what it was called when you could bend your thumb joint backwards beyond the typical range. It’s called a hitchhiker’s thumb because it resembles what a person’s thumb looks like if they’re trying to hitch a ride on the side of the road.

Her health class had been talking about genes and traits that can get passed on from your parents, such as the color of your hair and eyes or a tendency for disease, and the teacher brought up hitchhiker’s thumb. Turns out she was the only one in her health class who had one, so she was something of a minor celebrity during the class period. 

She also informed me the gene that controls how far back your thumb joint can go is called the ‘bendy thumb gene,’ which of course I thought was hilarious.

I’ve always been able to bend my thumbs backwards at the joint nearly 90 degrees. I thought everyone could do it, I had no idea it was something unusual let alone that it had a name. 

Hitchhiker’s thumb is believed to be passed on by your parents, but my mom can’t do it at all and my dad only part way. I can also raise one eyebrow at a time and sometimes when I hear an unexpected loud noise it feels like my ears are perking up. 

Apparently there are lots of weird things that can get passed on from your parents, such as rolling your tongue and the ability to smell ‘asparagus urine’ (I can unfortunately do both.)

Sometimes even irrational fears can be inherited by our ancestors, so someone down my family line might be to blame for my claustrophobia and fear of spiders and heights. Weird.

Our genetics make us unique, which makes life interesting. And if I ever have the need to hitchhike I guess I’ll have an advantage.