We often think of common diseases and rare diseases as unrelated. However, that type of thinking holds us back from discovering the links between the two.
Many rare diseases have unexpected connections with common diseases. These relationships can lead us to treatments not only for these rare diseases, but also more and better treatments for common diseases. Learn how rare diseases can advance common disease treatments.
Research and clinical trials for rare diseases have many unique challenges. Many of them do, though, have unexpected connections with common diseases. These relationships can lead us to more and better treatments for common diseases, as well as more effective treatments for rare diseases.
At PRA, our Center for Rare Diseases team is devoted to learning more about rare diseases. We work to create more options for rare disease patients and simultaneously communicate our findings to further common disease research.
Why Do We Study Rare Diseases?
Over 90% of rare diseases have no approved treatment, even as millions of people live with them worldwide. Patient Advocacy Organizations (PAOs) have played a significant role in drug development for rare disease patient communities. These PAOs are the nucleus of each rare disease patient community. They serve their communities in many ways, including raising awareness for the disease, raising funds for the community, and being an invaluable partner to drug developers. Because the PAO is a trusted resource for the community, they are also able to raise awareness of clinical development programs, communicating with patients through dedicated channels.
People with rare diseases often see a reduced quality of life, partly the consequence of managing complex disease with too little information. Many of these people develop disabilities, experience chronic pain, or have other issues that make daily tasks harder to accomplish. When we study rare diseases, we have the potential to help people live more independently with reduced pain and even extend life expectancy.
Rare disease research has less competition in the industry than common diseases. That means rare disease researchers are more likely to offer new information that can help patients and medical professionals understand rare conditions. These insights can help determine risk factors, genetic mutations, and other components that contribute to the development of a disease. Sometimes, we can link rare and common diseases by recognizing these factors, making communication within the industry even more critical.
Finding Genetic Clues to Advance Disease Research
We study rare diseases primarily to help the patients and families living with them. We must also consider that rare and non-rare diseases can result from similar factors in the body. Studying a rare disease can give us clues about the cause of other, more common illnesses.
Seeing the connection between common disease and rare disease sometimes occurs when they share a common genetic mutation. For example, Gaucher disease is a rare metabolic disorder that creates an enzyme deficiency and causes a buildup of specific lipids throughout the body.
Through the gene GBA1, we have found a genetic link between Gaucher disease and Parkinson’s disease, as well as other Lewy Body disorders, including Lewy Body dementia. GBA1 encodes glucocerebrosidase, the lysosomal enzyme in which Gaucher patients are deficient. Lewy body disease risk factors are linked specifically to GBA1 mutations. While the diseases aren’t all the same, this discovery points to possible commonalities between Gaucher and more common diseases like Alzheimer’s.
Many rare diseases come from a single genetic mutation. Once we find the source, we learn why the disease exists, and we have a starting point for unraveling the disease mechanism and ultimately finding a meaningful treatment.
Making Connections Between Rare and Common Diseases
We can also make connections by analyzing consequences to gene mutations. That makes it easier to isolate specific effects of genetic mutations and understand how they impact other diseases, like diabetes or certain cancers, which often arise due to several different mutations. This deeper understanding can show us how various genetic functions interact with the mutated gene and how the disease alters the body’s function as a whole.
Some rare disease discoveries have also opened up new research opportunities as we gain a better understanding of how the body changes in the face of different diseases.
For instance, genetic differences in the NT5E gene that cause Arterial Calcifications due to Deficiency in CD73 (ACDC), a rare condition that creates calcification in the arms and legs, has given us a new understanding of calcification related to advanced kidney disease. A mannosyl-oligosaccharide glycosidase (MOGS) gene defect similarly causes a neurological disease that has only affected three children worldwide so far. The disease lowers antibodies but increases resistance to specific viral infections. Studying this phenomenon has helped us gain insight into how the immune system works when responding to viruses like the common cold.
These results show us that even if a disease is rare, it can contribute to common disease research. Rare disease research can also help us break down the big picture and hone in on specific areas of common diseases when several different components are present.
PRA’s Center for Rare Diseases works to identify various factors associated with rare diseases. We help rare disease patients understand their conditions while furthering research beyond our center by working with researchers and medical professionals around the world.
RARE DISEASES NEWSLETTER Volume 8, January 2018
This quarterly publication will keep you up to date on PRA’s Rare Disease Team focus, achievements, and new initiatives.
The Importance of Patient Education for Rare Disease Trials
Patient-Centric Protocol Risk Assessment Tool
Expert-validated tool that enables sponsors to identify potential trial efficiency risks driven by participation burden in any draft protocol