In my last article, ‘understanding autoimmune disease’, I discussed the various elements that are at play in autoimmune disorders. These complex diseases which can be both systemic (affecting various parts of the body in similar ways) or organ specific (predominantly affecting one organ) are difficult to pinpoint to one underlying cause. However, what we do understand is that genetics, environmental factors and a breakdown of our bodily defences may contribute to the onset of these conditions. In this article, I will consider the genetic aspect of this picture, and debate whether there really is an inheritable gene for autoimmune disease?
Several people in my family have autoimmune disorders including my parents, siblings, aunts and grandparents. Is this a coincidence or do we all carry a gene that codes for autoimmune disease?
Autoimmune disease encompasses a variety of different conditions which present with differing symptoms. Scientific studies have found that autoimmune disease is evident within certain families, increasing the risk factor for developing an autoimmune disease if someone in your family suffers from one. What isn’t clear, is whether specific autoimmune disorders, such as multiple sclerosis, can be inherited or whether it’s the underlying risk factors that are passed on and the presentation of the distinct autoimmune disease is dependent on other factors such as environment and lifestyle.
The cause of autoimmune disease is multifactorial, and this is true for the associated genetic predisposition to the conditions as well. So no, reflecting to the title of this article, it is highly unlikely that there is one gene that causes autoimmune disease. It is more likely that the combination of gene variations in unison creates an ecosystem where under certain disruptive conditions autoimmunity can take effect. As the research in genetic variations and disease presentation develops it is likely that we will have a better understanding of which genetic variations are important in autoimmune disease.
Current research suggests that genes involved in the immune response are most influential in autoimmune disease. The fragility of the complex immune system relies of key messages from cells with defined roles in the body. For example, one particular cell (an antigen presenting cell) warns the body of foreign invaders so that it can start to build an immune response to this invader. If this cell sends the wrong message to the immune system, then the immune system might not target the foreign invader but targets an innocent cell in the pancreas instead which can lead to diabetes. Studies have demonstrated that genetic variations in these alerting antigen presenting cells are associated with autoimmune diseases in families.
I would also postulate that genetic variations in genes that are involved in methylation pathways and detoxification are linked to autoimmune disease, as it is understood that some autoimmune disorders are caused by the affected self-organ or system being caught in the crossfire.
Issues in methylation and detoxification can cause ‘oxidative stress’ which broadly causes cells to alert the immune system that there is an issue in this part of the body (wherever the oxidative stress is present) and the immune system fires up an attack in response causing inflammation. In turn, the inflammation then can cause destruction to that area of the body (self-tissue). For example, demyelination in multiple sclerosis is seen when there is inflammation in the central nervous system which may be due to oxidative stress created upstream by fundamental issues with functionality at the cell level.
Should you consider your genetics in autoimmune disease?
There may not be one gene associated with autoimmunity, but it is certainly helpful to know what your genetic risk factors or weaknesses are, as this will help to determine possible underlying causes of autoimmune conditions. It also helps to take preventative measures in your life when you know that there are certain areas where you body might not function as optimally as it could.
Genetics is a small piece of the jigsaw, and only when this is considered holistically with other pieces of the puzzle can you begin to get an understanding of your risk factors. In knowing this, you can then work with a health practitioner to explore possible nutritional therapies and lifestyle practices that will support your symptoms and promote your wellbeing.
In next week’s article, I will be discussing the role of pathogens in autoimmune disease and how you can take action against this. Autoimmune conditions are often viewed as self-destructing diseases with no pathogenic cause, but as evidence evolves we are seeing that bacteria, viruses and parasites may play a vital role in these immune inhibiting disorders.