Hi! I have ALS family history. I know that my grandfather died from ALS in the age of 51. Then his daughter (my mom) died from FTD in the age of 48, her sister is healthy. Now I am 40, and I have a sister, 31 y.o. I have read tons of material about it. I know that this can pass down the family line 50%. But it's just a theory. In my research of examples of ALS manifestations in 3 family generations, I have not seen a generation where ALS would not have manifested. If it's 2 kids, at least one (very often both) got sick. If it's 3 kids, of course 2 were sick. It's like it doesn't skip. Also I noticed that in all examples elder kid got sick. All this is telling me that actual probability is much higher than 50%, I just have a feeling sometimes that I am doomed. Does anyone know a genetic aspect of ALS. I would appreciate if you share your knowledge. Thank you.