According to a story from Charcot-Marie-Tooth News, a team of scientists have successfully identified four new mutations that are capable of causing Charcot-Marie-Tooth disease. These mutations affect the GJB1 gene. These new findings add to the growing list of over 90 genes that, when mutated, can cause the illness. The amount of individual mutations that have been identified is even higher, running into the hundreds.
About Charcot-Marie-Tooth Disease
Charcot-Marie-Tooth disease is a hereditary disorder of the peripheral nervous system. It is most characterized by a progressive loss of touch sensation and muscle tissue in several different parts of the body. The cause of this disease is usually linked to a genetic mutation, but the mutation involved varies depending on the variant of Charcot-Marie-Tooth disease. There are multiple types of Charcot-Marie-Tooth disease, with all types aside from type 2 having a demyelinization effect. Type 2 causes damage to the neuronal axon instead. Symptoms include foot drop, muscle wasting (typically in the arms, legs, and hands), painful muscle spasms, loss of sensation in the limbs, scoliosis, trouble speaking, chewing, swallowing, and tremors. Treatment typically includes therapy and surgery in order to maintain function. There is no cure. The disease can occur early in life or as late as the 30s and 40s. To learn more about Charcot-Marie-Tooth disease, click here.
About The Research
In this study, the researchers looked at 12 patients from Brazil from five different families. All of these patients were presenting with symptoms that the scientists determined were mild to moderate. A sequencing of each patient’s GJB1 gene allowed the researchers to identify five mutations in total; however, only four were determined to be linked to the disease.
These mutations were more specifically connected to a variant of Charcot-Marie-Tooth disease called 1X. As the male patients appeared to have more severe symptoms, this pointed to the likelihood that an X-linked form of the disease was present.
The discovery continues to add a further wrinkle to the exceptional genetic variability that has come to characterize the GJB1 gene. The study was originally published in the scientific journal Journal of the Peripheral Nervous System. You can find it here.
