Around 10% of people diagnosed with MND have a ‘familial’ form of the condition; meaning there are two or more affected members within their family. Most people diagnosed with MND have what is called ‘sporadic’ MND, so although there may be a genetic element involved, other family members will not be affected.
The inherited form of MND can be passed on in future generations and so can affect multiple family members over time. People who have this form of MND have inherited an error in their genetic instructions from one of their parents. This error is called a mutation and it causes the gene that contains the error to work incorrectly.
There is a 50/50 chance that the next generation of the family will inherit the MND-related gene and so they will have a higher chance of developing MND during their lifetime. This fact sheet produced by the MND UK Association explains more about inherited MND and family tree diagrams: Introduction to inherited MND
However, not all people who have an MND-related genetic mutation will develop MND, and research continues to try to understand why this is. One theory, the multistep hypothesis, tries to explain the possible reasons why some people are more likely to develop MND than others, you can read more about this theory here: Steps to understanding MND - MND Research Blog
If more than one member of your family has been diagnosed with MND then you may wish to find out more about genetic testing. Genetic testing allows people with a family history of MND to check if they have also inherited a faulty gene.
It is a very personal choice to decide whether to undergo genetic testing, and this is a process that includes speaking with a genetic counsellor to discuss the implications of these tests. You can find out more about genetic testing here: Familial MND and genetic testing
People who are carrying an MND gene mutation
If you undergo genetic counselling and genetic testing and are found to be carrying a known MND related gene, this can be confronting news and may take some time to come to terms with. Your genetic counsellor and doctor should be able to discuss this further with you and answer any questions you may have. They can also offer further support if needed, such as a referral to a psychologist.
MND Genies is an online support network and Facebook group for people who have a motor neurone disease related genetic mutation, but do not have MND. You can find out more and request to join here: MND Genies
If you are planning to have children, there are options available to you that can reduce the chances of you passing on an MND related faulty gene. Pre-implantation genetic testing (PGT) – also known as pre-implantation genetic diagnosis (PGD), is an advanced screening technique that can be used alongside in vitro fertilization (IVF). IVF is a procedure where an egg and sperm cell are combined outside the body before the fertilised egg is implanted into the uterus.
If you have already identified the faulty gene that runs within your family, pre-implantation genetic testing can be used to screen your fertilised egg to check if it is has the faulty gene. Using this technique, you can ensure that the embryo that will be used for your pregnancy does not have an MND related gene mutation.
This screening technique has the potential to stop MND in future generations of your family and as of the 1st of November 2021 is available as part of the Medicare Benefits Schedule. This means that eligible Australians with a high risk of having a child affected by a genetic disorder, will be able to receive a Medicare rebate for accessing pre-implantation genetic testing.
Although this may not cover all costs involved with IVF and PGT, it is a welcome addition to the Medicare benefits scheme and will hopefully allow more individuals to have choice and control over their genetic future. You can read the Department of Health update here: Factsheet-pre-imp-gentes.mbsonline.gov.au
To find out more about your options with IVF and PGT, and the Medicare rebates available, please speak to your doctor or genetic counsellor. You can read more about IVF rebates on the NSW Health website here: Improving affordability and access to IVF services in NSW and here: Apply for the Pre-IVF Fertility Testing Rebate | Service NSW.
To read more about PGT and the associated costs, visit IVF Australia here: Pre-implantation genetic testing
The International Alliance of ALS/MND Associations hosted a series of webinars covering a range of topics that people within the MND community may find interesting. Two of the recently recorded webinars have focused on the role of genetics in MND.
Introduction to MND Genetics - Introduction to ALS/MND Genetics - YouTube
This webinar recorded in October 2021 will provide you with an overview of genetic inheritance and the current understanding of genetics related to MND. The presenters include:
- Dr Kelly Williams, a Senior Research Fellow at the Centre for MND Research at Macquarie University, Sydney. Kelly Williams — Macquarie University
- Professor Ammar Al-Chalabi, a Professor of Neurology and Complex Disease Genetics, Consultant Neurologist and Director of the MND Care and Research Centre at King's College London. Prof Ammar Al-Chalabi - King's College
Genetics – Counselling & Testing: Genetics – Counselling & Testing - YouTube
This webinar recorded in October 2021 will provide you with an overview of what is involved in genetics counselling & genetic testing in relation to MND. The presenters include:
- Dr Adriano Chio, Professor of Neurology and Director of the ALS Centre in Torino, Italy. Prof. Adriano Chio
- Jennifer Roggenbuck, Assistant Professor and Genetic Counsellor at Ohio State University Wexner Medical Centre. Jennifer Roggenbuck
- Dr Alsidair McNeil, Senior Clinical Lecturer in Neurogenetics & Consultant in Clinical Genetics at Sheffield Children’s Hospital. Dr Alisdair McNeill