Congenital mirror movements (CMM) are characterized by voluntary movements on one side of the body that mirror involuntary movements on the opposite side. This condition typically manifests from early childhood, predominantly affecting the arms and hands. Individuals with CMM often experience difficulties performing tasks that require precise unilateral hand movements, such as opening a water bottle or driving a manual car. During the crossing of fibers in the cortical spinal tract (CST), there are normal crossed fibers and abnormal crossed fibers. Mutations in genes will lead to abnormal wiring, where the axons do not cross the midline properly and the defective genes will send erroneous signals to the limb. The study aims to identify the specific mutations (pathogenic variants) responsible for mirror movements to enhance the understanding of the genetic basis of this rare disorder. Under the guidance of Dr. Myriam Srour, Pediatric Neurologist and Clinician-Scientist at the Montreal Children's Hospital, my main responsibilities in the lab are to extract the DNA used to analyze the various mutations through exome sequencing.