The science of next-generation sequencing technology has enabled the discovery of a new genetic cause of CMT1, the most prevalent form of Charcot-Marie-Tooth disease, according to researchers from the department of neurology at University of Pennsylvania’s Perlman School of Medicine and the Children’s Hospital of Philadelphia. The findings expand the number of genes known to cause CMT1 and advances neurologists’ understanding of the genetic bases for the neuropathy. Charcot-Marie-Tooth Disease, affecting about 1 in 2500 patients in the US, is a progressive neurodegenerative disorder that causes numbness and weakness in the hands and feet. The team’s findings are published online in the journal Brain.
CMT can be caused by the loss of axons in the peripheral nerves (CMT2) or by a malfunction in the Schwann cells that comprise the myelin sheath (CMT1). The study team examined a father and son with CMT1 who did not carry a mutation of any of the 5 genes presently known to cause the condition. There was no prior history of CMT1 in the father’s family, suggesting the presence of a new random mutation that had then been passed on. Next-generation sequencing technology enabled the genetic sequencing of the father’s 20,000 genes, and identification of the specific mutation responsible for his condition, which was then passed on to his son. “We are fortunate to have these tools to help us provide genetic diagnoses to our patients, sometimes even in cases where the patients have no mutations in known causes of their disease.” Said lead author, William Motley, MD, “Traditional genetic techniques would never have allowed us to find the cause of this family’s CMT.”
Read more about the findings here.
The journal article summary may be read here.