The chances of that are vanishingly small. I have seven siblings. The eight of us have a total of 34 children. If there were a dominant gene, even if its expression is unusually mild, one of those children would certainly have some weird neurological problems! Even the possibility that I have a de novo dominant mutation is slim, since I have seven kids myself.

Abby

An image came to me of a few of us sitting in a room with a bunch of doctors and scientists and grilling them for hours. How fun would that be?

I think your plan sounds sensible. Might a muscle biopsy be something to do in the meantime? What's one more scar?

Heck, I don't mind. But my neurologist--this was back while they were still trying to diagnose me--said he's really reluctant to do a muscle biopsy, because they often come back confusing, and people get diagnosed with conditions they don't actually have. From what I've read since--anecdotally, mostly here--that seems to be the case.

OK, so I have been looking through FaceBook albums of my siblings for droopy eyelids, and I discovered SEVEN photos of one nephew, age one and a half, with a droopy right eyelid. The first one was so pronounced that I thought it must have just been a fluke of the camera, but then I found the others. There are also dozens in which his eyes are symmetrical. As far as I know, there are no health concerns about him--didn't have trouble eating, didn't walk late, nothing like that. He seemed like a normal toddler to me when I saw him recently. He is my brother's son. My brother has always been energetic, and he works construction.

I am just barely wise enough not to call my sister-in-law and bring up CMS (just barely), but I will certainly be paying attention.

Abby

And here's what I think Mayo might do . . . they might say that you have "familial ptosis," that it's benign and that you don't need any treatment. They like to undiagnose adults.

from the PDF attached to Annie's post, above

"...asymmetric ptosis is most often associated with
acquired and autoimmune myasthenia gravis (MG) in
contrast to CMS and other inherited disorders. He and
his coworkers studied the diagnostic value of this
observation by comparing a group of patients with
autoimmune MG or Lambert–Eaton myasthenic syndrome
(LEMS) with a group of patients with hereditary
myopathy. Studying the files of 250 MG or LEMS
D. Beeson et al. / Neuromuscular Disorders 15 (2005) 498–512 505
patients and 83 hereditary myopathy or CMS patients
(dystrophic myotonia, progressive external ophthalmoplegia,
oculopharyngeal muscle dystrophy, CMS) revealed a
similar frequency of ptosis in both groups (76 and 78%,
respectively). Asymmetry was noted in 80% of the MG
or LEMS patients and in 30% of the myopathy or CMS
patients. To verify these findings, a prospective study
was started in which the ptosis was quantified using
digital photography. So far, 52% of 23 MG patients and
none of 20 myopathy/CMS patients were found to have a
significant asymmetric ptosis. The results of these
ongoing studies suggest that asymmetric ptosis points
to an underlying autoimmune disease and less likely
towards a hereditary myopathy or CMS."