Genes involved in BRAIN COMMUNICATION (ion channel function)
• Ion channels are proteins that allow the brain cells to communicate with electricity. When there are problems with the ion channels, there may be excessive electrical activity (hyperexcitability) and this might result in epilepsy
• Not all mutations will cause health problems like epilepsy. There are degrees of severity associated with different mutated genes. We can call them abnormal “Strong” versus ‘weak” mutated genes
• “Strong” genes are biologically very important to health. Therefore mutated strong genes have obviously “bad” effects
- Strong mutated genes are rare
* However when they occur in a family, the can occur very commonly in the family tree since they are very important to normal health
* An example is “tuberous sclerosis” which is a genetic condition associated with a “strong” mutated genes.
* “Strong” bad genes account for very few cases of epilepsy
* Genetic testing is sometimes possible for “strong” genes
• “Weak” mutated genes may not be powerful enough to cause epilepsy alone, because they are not biologically essential to health, but may be an influencing factor, with other genes or environmental conditions
- Families who have abnormal “weak” genes do not tend to have a lot of affected cases in the family tree. There is a sense though that the disorder “runs in the family”
- This is true for most medical diseases, e.g. high blood pressure. This is also called “complex inheritance”
- Genetic testing is usually not possible for weak genes