Neurogenetics

​Genetic disorders are a group of different diseases that can be passed down from one generation to the next. Genes are the “building blocks” which make up the code that determines who we are as a person. Each gene is responsible for coding a protein, and each protein has a specific function in the body. When these genes have a mutation, it can result in a protein that is functional, less functional, or absent. If the protein is absent or less functional, you may have symptoms that result in your being diagnosed with a disease. Many neurological disorders have a genetic basis, and as such, if a genetic disorder is suspected as the cause of your disease, you may be referred for genetic testing.

Genetic tests determine if a patient’s condition was likely caused by a mutated gene, the likelihood of passing the gene on to their children and if healthy family members also carry the gene and are at risk of developing the disease.

There are a broad range of neurological conditions that are hereditary. These can range from nerve disorders (e.g. Charcot Marie Tooth), to muscle disorders (e.g. Muscular Dystrophies), to disorders that affect the brain and spinal cord (e.g. Spinocerebellar Ataxia). Many disorders involving mitochondria (our energy units), and our breakdown of food products (metabolic disorders) can also have neurological manifestations. 

Clinicians usually recommend that the extended family gets tested for the gene if more than one family member has been diagnosed with the same condition, because this is a sign of a genetic cause. This would include siblings and children of siblings, whether they are already showing symptoms or not. However, each patient and family member must decide whether or not to proceed with testing, based on their own circumstances and priorities. In this day and age, knowing the results of genetic testing may affect their family planning decisions and help them understand the disease including how it will likely progress.

Genetic testing has implications on the individual, family members, and family planning. Your genetic counsellor can facilitate family discussions on the next steps to ensure family goals are met, and to protect the wishes of all parties. This includes recommendations on who else in the family should get tested, non-disclosure of results if requested, and family planning options - such as preimplantation genetic diagnosis (PGD) to prevent the disease-causing gene from being passed down to the next generation.

With the advancement in technology, new treatments and options for reproduction are available. Knowing if you have the condition and if it can be passed to your children allows you to take necessary actions and make plans that are best for you and your family. Even if no treatments are available, finding out the genetic cause helps advance science and develop new drugs to target diseases.

There can be considerable social and psychological effects of genetic testing – particularly if there are no treatments available for the condition. Different people react differently to their genetic results. It is possible that you may experience guilt about having the disorder, or passing the disorder down to your children. There also may be a sense of frustration or helplessness that comes with knowing that you have an incurable condition. However, you may also feel that you have a better sense of control by being in the know of your genetic status and a sense of relief if the results come back negative. There can also be implications to insurance coverage for yourself or for your extended family members.