Why mutations in different genes cause the same disease across different familie - (Jun/07/2016 )

Diseases can have both genetic and environmental components responsible. In some complex inheritance following diseases, a single gene is not responsible for the disease across different cohorts. Considering the example of epilepsy, even when it is monogenic, not only different mutations of a single gene but totally different genes can be responsible for the disease in different families. Why is it so? How can such a variety of genes cause the same disease? What kind of inheritance pattern is this?

you shouldn't lump epilepsy as one "disease". there are many different forms and causes of epilepsy ranging from genetic to injury and combinations.

other "diseases" and conditions may have similar causes.

mdfenko on Tue Jun 7 11:54:02 2016 said:

you shouldn't lump epilepsy as one "disease". there are many different forms and causes of epilepsy ranging from genetic to injury and combinations.

 

other "diseases" and conditions may have similar causes.

Okay, so if we become more focused and consider just one kind of Epilepsy, even then, in different cohorts and even in different families of same geographical-cultural location, altogether different genes can mutate to cause the same symptoms, same disease. Why is it so?

same symptoms doesn't necessarily indicate the same disease.

when you say "one kind of epilepsy" are you saying the way it apparently manifests? or do you have any specific knowledge that it starts at the exact same area of the brain and expands the same way?

do you have specific knowledge of the genotypes of the afflicted families?