My Dad developed MD in his late 20s, about 60 years ago. His, and most of his siblings', was due to genetics. We've been checked all thru our lives and not of us have signs. However, we've all worn glasses since childhood.

Wonder why it happens later on in "boomers'" lives now.

As kids, we learned to live with a disabled Dad. Mom used to say "Your dad can see more than you know"! He's done extremely well, had to stop driving in the late 60's and Mom had to get her licenses in her 30s to take over.