Category: Clinical Sciences/Health Conditions
A molecular panel of 79 expanded genes was requested for Charcot Marie Tooth in our patient. We found a mutation in the homozygous type GJB1 gene that causes a deletion of thymine at position 54 of the coding region of the GJB1 gene. The same study was applied to the patient's mother showing the same mutation. Therefore, the case presented suggests a mother to son inheritance pattern.
A 23 year old male patient with family history of cavus foot and weakness of lower limbs. He began with hand tremors and finger weakness then showed muscle fatigue, steppage gait, falls and balance failures. The first electro-diagnostic study showed Intermediate Charcot-Marie-Tooth pattern. Studies included MRI, metabolic profile and autoimmunity profile, which were normal; The first molecular study for PMP22 gene wasn't conclusive so a molecular panel of 79 expanded genes was requested, finding a homozygous mutation in the GJB1 gene. He completed his rehabilitation without complications and he is currently an industrial engineer and performs sport.
Charcot-Marie-Tooth disease (CMT), is an inherited, autosomal dominant disease, caused by duplication in the peripheral myelin protein 22 gene (PMP22) in 40-50% of cases. However, mutations in the GJB1 gene correspond to 10-20% of cases. The GJB1 gene is related to a variant linked to the X chromosome. Due to the genetic variability of hereditary neuropathies, genetic studies are part of the diagnostic algorithm.
Is important to recognize the X-linked CMT and his genetics in the men with neuropathy findings , emphasize the importance of recognition, timely diagnosis and therapeutic approach according to the experience through multidisciplinary rehabilitation.
It is important to know the genetic variants and their clinical presentation to arrive at a correct diagnosis. The CTMX phenotype is an uncommon variant, with mutation of the GJB1 gene of which few cases have been reported.
Iván González– Resident of Physical Medicine and Rehabilitation, Universidad de La Sabana
Mariana Muñoz Rodriguez– Resident of Physical Medicine and Rehabilitation, Universidad de La Sabana
Laura McCormick Useche– Resident of Physical Medicine and Rehabilitation, Universidad de La Sabana
Luisa Vasquez Fernandez– Resident of Physical Medicine and Rehabilitation, Universidad de La Sabana
Claudia Mondragón Rinta– Physiatry, Clinica Universidad de La Sabana
Maria Gomez Guevara– Physiatry, Clinica Universidad de La Sabana