ALS and heredity

[grp_believes_in_God]

I have read about 5 to 10% of all ALS cases are inherited. What does that mean? that 10% of people who have als, their children will get als too ? I am looking at my twitches quite differently after I heard of my dad's diagnosed. Frankly its freaking me out and i am considering getting it checked. Anyone has any thoughts on what the children of pals can do in terms of early detection and / or monitoring ?

 

[rcharlton]

There are two types of ALS - hereditary and sporadic.

Roughly 10% of ALS cases are hereditary. This means that there is some genetic trait being passed from generation to generation which makes children of a person afflicted with the hereditary form of ALS more pre-disposed to developing ALS. In other words there is a family history of ALS and there is a very high risk that the children will develop ALS..

The balance of PALS have a sporadic form of ALS. There is no evidence of any hereditary elements to sporadic ALS - meaning the children of a person afflicted with the sporadic form of ALS are NOT more likely to develop ALS.

So unless you have a family history of ALS other than your dad - you have nothing to worry about.

 

[grp_believes_in_God]

thx rcharlton, that helps. So in case of the 10% familial als, does every generation gets it or can it skip generations? To my knowledge, none of my relatives in my mom and dad's family have it or their parents. I don't know about the generaion before that though. Is there any test to check whether you are carrying that gene ?

 

[Al]

From what I understand they have identified the SOD1 gene that is in familial cases of ALS. Not sure if it is a readilly available test yet. Anybody else have any information? One thing I am not sure about is whether being the first one with sporadic: is it possible that I am the first one in the heredity pool? A good question for my Neuro on my next visit.

 

[Meg1]

Al --

Sporadic ALS is not known to be caused by a genetic mutation that can be passed on to descendants (although it is thought to have some genetic component). You cannot be the first person in your family to have familial ALS.

grp --

Familial ALS is an autosomal dominant disease. That means that only a gene carrier can pass on the gene causing ALS and that everyone who carries the gene will eventually get the disease. The chance of each child of a victim of familial ALS having the ALS gene is 50%. If I read your post correctly, your father has been diagnosed with ALS but you know of no other family members who have had the disease. If both your father's parents lived to ripe old ages, you're almost certainly in the clear as far as FALS goes.