Our study provides the first molecular and cellular evidence for myelination deficits in Williams syndrome (WS) linked to Gtf2i deletion in neurons. We are interested in further validating the translational aspect of the novel pathophysiological myelination deficits we found. To achieve this, we plan to further characterize myelination deficits in WS human patients. We aim to do this by (a) measuring their neuronal conductivity utilizing a number of conductivity tests; (b) measuring motor skills properties by a parent-validated questionnaire and the GAITRite walkway, and (c) define white matter abnormalities by MRI scans of WS patients. Upon this, we aim to treat WS patients with 4-ap, an FDA-approved drug that increases axonal conductivity and test its effects on fine motor skills, cognitive capabilities and social behavior.