What causes Tuberous Sclerosis Complex (TSC)?

A change (mutation/pathogenic varient) in the TSC1 or TSC2 gene, which normally suppress cell growth, lead to abnormal tissue and tumor growth causing Tuberous Sclerosis Complex (TSC). Only one of the genes needs to be affected for TSC to be present. The TSC1 gene is located on chromosome 9. The TSC2 gene is located on chromosome 16. TSC is autosomal dominant which means males and females  have an equal risk of having the condition.

A child can inherit TSC if either parent has it. A parent with tuberous sclerosis has a 50 percent chance of passing the condition to their children.

About one-third of people with TSC inherited the genetic condition from a parent. However, for the other two-thirds,70% the condition is "spontaneous," meaning that the change is the first time of that change in the child's family.

Sometimes it is found that a child with TSC has a parent who also has the condition but didn’t know it. If your child is diagnosed with TSC, you may want to check that you dont also have it.

If you have one child with TSC, there is an increased chance that your other children will also have the condition.

More informatio about the genetics of TSC https://www.tscalliance.org/understanding-tsc/genetics/

More information on autosomal dominant inheritance https://www.genomicseducation.hee.nhs.uk/genotes/knowledge-hub/autosomal-dominant-inheritance/

How common is TSC?

TSC affects approximately 1: 6,000 live births. It is estimated there are between 1-2 million people in the world living with TSC

Can it be cured?

There is no cure, but symptoms are managed with medications (like mTOR inhibitors for tumors), therapies (physical, occupational, speech), and sometimes surgery for tumors or severe epilepsy. There are international clinical consensus guidlines for the dignosis, surveillance and management of the symptoms. (See section on Diagnosis & Management)

What's the outlook?

TSC varies widely from affecting people mildly to very severely and symptoms change over time; many live full lives though some can face severe challenges. https://www.ninds.nih.gov/health-information/disorders/tuberous-sclerosis-complex

Medication Information

Medicines.ie, is Ireland’s central, regulator approved online resource of accurate information on medicines available in the Republic of Ireland.

It provides information for healthcare professionals and the public through Summary of Product Characteristics (SPCs), Patient Information Leaflets (PILs) and Educational Materials. It is owned by the Irish Pharmaceutical Healhcare Association (IPHA) and designed for easy searching and accessing crutiol drug details https://www.medicines.ie/

Where can I find more information about TSC?

There are excellent websites hosted by TSC organisaitons worldwide where you will find extensive and comprehasive information resources and direction. We highly recommend you visit them.

TSCAlliance https://www.tscalliance.org/

Tuberous Sclerosis Association UK TSA UK https://tuberous-sclerosis.org/

Tuberous Sclerosis Australia https://tsa.org.au/

Glossary

Autosomal: means traits or conditions are linked to non-sex chromosomes, affecting all genders equally, unlike sex linked traits https://www.genome.gov/genetics-glossary/Autosomal-Dominant-Disorder

https://www.genomicseducation.hee.nhs.uk/genotes/knowledge-hub/autosomal-dominant-inheritance/

DNA: Deoxyribonucleic Acid, is the molecule carrying genetic instructions for life, forming a double helix structure like a twisted ladder. The sequence of these bases encodes genes, which direct the building and functioning of all organisms, determining traits and passing hereditary information from parents to offspring. https://www.genome.gov/genetics-glossary/Deoxyribonucleic-Acid-DNA#:~:text=Deoxyribonucleic%20acid%20(abbreviated%20DNA)%20is,a%20protein%20or%20RNA%20molecule.

Gene: A gene is a stretch of DNA containing a sequence (instruction) with a particular function, such as to make a specific protein. https://www.genomicseducation.hee.nhs.uk/genotes/knowledge-hub/gene/

TSC1 gene: