About Laing Distal Myopathy
The New York Center for Rare Diseases supports the mission and guidelines of the Genetic and Rare Diseases Information Center (GARD). The following information is provided by the NIH.
Summary
Laing distal myopathy is a slowly progressive muscle disorder that tends to begin in childhood. Early symptoms include weakness in the feet and ankles, followed by weakness in the hands and wrists. Weakness in the feet leads to tightening of the Achilles tendon, an inability to lift the big toe, and a high-stepping walk. Weakness in the hands makes it more difficult to lift the fingers, especially the third and fourth fingers. Other findings include scoliosis and cardiomyopathy in up to one third of individuals. Most affected people remain mobile throughout life. Laing distal myopathy is caused by genetic changes in the MYH7 gene and is inherited in an autosomal dominant fashion.
Causes
What Causes This Disease?
Genetic Mutations: Laing early-onset distal myopathy is caused by genetic mutations, also known as pathogenic variants. Genetic mutations can be hereditary, when parents pass them down to their children, or they may occur randomly when cells are dividing. Genetic mutations may also result from contracted viruses, environmental factors, such as UV radiation from sunlight exposure, or a combination of any of these.
If you suspect you may have this disease, you may want to start collecting your family health history. Information such as other family members who have had similar symptoms, when their/your symptoms first appeared, or exposures to any potential disease-causing environmental factors should be discussed with your medical team.
Known Genetic Mutations:
Laing early-onset distal myopathy is caused by genetic mutations in the following known gene(s):
MYH7
Given these known genetic mutation(s), you may want to ask your health care team if genetic testing is right for you. Genetic tests are laboratory tests that use samples of blood, saliva, or other tissues to help identify changes in genes, chromosomes, or proteins. Genetic testing can help confirm or rule out a suspected genetic disease, or can provide other useful information to your health care team.
Can This Disease Be Passed Down From Parent to Child?
Yes. It is possible for a biological parent to pass down genetic mutations that cause or increase the chances of getting this disease to their child. This is known as inheritance. Knowing whether other family members have previously had this disease, also known as family health history, can be very important information for your medical team.
There are multiple ways, or patterns, a disease can be inherited depending on the gene(s) involved. Based on GARD’s current data, this disease can be inherited in the following pattern(s):
Autosomal Dominant: Autosomal means the gene involved is located on one of the numbered chromosomes. Dominant means that a child only needs to inherit one copy of the mutated gene, from either biological parent, to be affected by the disease.
People affected by an autosomal dominant disease have a 50% chance of passing on the mutated gene to their biological child.