Expert Reviewed By: Dr. Brandon Colby MD
Familial Atypical Mycobacteriosis (FAM) is a rare genetic disorder that affects the immune system, making individuals more susceptible to infections caused by atypical mycobacteria. This article aims to provide an overview of FAM, its diagnosis, and the role of genetic testing in managing this disease. With a better understanding of the condition, patients and their families can make informed decisions about their healthcare and treatment options.
Unraveling the Complexities of Familial Atypical Mycobacteriosis
FAM is an autosomal dominant disorder, which means that an affected individual has a 50% chance of passing the condition on to their children. The disorder is caused by mutations in the interferon-gamma receptor 1 (IFNGR1) or interferon-gamma receptor 2 (IFNGR2) genes. These genes play an essential role in the immune system's response to infections, particularly those caused by atypical mycobacteria.
Atypical mycobacteria are a group of bacteria that are closely related to the bacteria that cause tuberculosis and leprosy. However, these bacteria are generally less harmful and can be found in various environments, such as soil and water. In individuals with FAM, the immune system is unable to effectively fight off these infections, leading to recurrent and severe infections.
Diagnosing Familial Atypical Mycobacteriosis
Diagnosing FAM can be challenging, as the symptoms of the disorder can vary widely among affected individuals. Common signs and symptoms of FAM include:
- Recurrent infections of the skin, lymph nodes, and lungs
- Non-healing skin ulcers
- Swollen lymph nodes
- Fever, weight loss, and fatigue
Due to the variability in symptoms, a thorough medical history and physical examination are crucial in the diagnostic process. Additionally, laboratory tests may be conducted to identify the presence of atypical mycobacteria and assess the immune system's function. However, genetic testing is the most definitive method for diagnosing FAM.
The Power of Genetic Testing in Familial Atypical Mycobacteriosis
Genetic testing can help confirm a diagnosis of FAM, provide valuable information for family planning, and guide appropriate treatment options. There are several uses of genetic testing in the context of FAM:
Diagnostic Testing
Diagnostic genetic testing is used to identify the presence of mutations in the IFNGR1 or IFNGR2 genes in individuals suspected of having FAM. This testing can confirm the diagnosis and help guide treatment decisions.
Carrier Testing
Carrier testing is performed on individuals who have a family history of FAM but do not show any signs or symptoms of the disorder. This testing can help determine if an individual is carrying a mutated gene and has a risk of passing it on to their children.
Prenatal Testing
Prenatal genetic testing can be performed on a developing fetus if there is a known risk of FAM in the family. This testing can help parents make informed decisions about their pregnancy and prepare for the potential needs of their child.
Preimplantation Genetic Diagnosis (PGD)
PGD is a specialized form of genetic testing performed on embryos created through in vitro fertilization (IVF). This testing can help identify embryos that carry the mutated gene, allowing parents to choose embryos without the mutation for implantation, thus preventing the transmission of FAM to their children.
Conclusion
Understanding Familial Atypical Mycobacteriosis is essential for individuals and families affected by this rare genetic disorder. Genetic testing plays a crucial role in diagnosing FAM and guiding treatment decisions, as well as providing information for family planning and prenatal care. By staying informed and utilizing the available resources, patients and their families can navigate the challenges of FAM and work towards a healthier future.
About The Expert Reviewer
Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of and the author of Outsmart Your Genes.
Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (ACMG), an Associate of the American College of Preventive Medicine (ACPM), and a member of the National Society of Genetic Counselors (NSGC)