Estrategias para el diagnóstico clínico y molecular de Charcot-Marie-Tooth 1A. Estudio en pacientes mexicanos

Background: Charcot-Marie-Tooth (CMT) is the most common inherited disorder of the human peripheral nerve. The most frequent subtype, CMT1A, is associated with duplication of ∼1.5 Mb fragment in 17p11-p12, that includes the PMP22 gene. Objective: The aim of this study was to describe different strategies used for clinical and molecular CMT1A diagnoses among patients attending the National Rehabilitation Institute of Mexico (INR). Material and methods: 17 patients had clinical and electrophysiological features compatible with CMT1. A molecular study using capillary electrophoresis (CE) was performed and a PMP22 gene duplication was detected. Results: Clinical, biochemical and electrophysiological studies constituted the inclusion criteria to establish a CMT1diagnosis. With CE the duplication of the PMP22 gene was observable and we established a possible CMT1A diagnosis in seven patients. All duplications detected by capillary electrophoresis were corroborated using FISH. Conclusion: CE is a feasible and reliable method to detect PMP22 gene duplication. Using different clinical, electrophysiological and molecular strategies in this patient population allowed us to establish an accurate diagnosis and offer suitable genetic counseling.