Duane syndrome is a congenital eye movement disorder caused by a failure of cranial nerve VI to develop normally, which leads to the inability to move the eyes from side to side (abduction refers to moving the eye toward the outside of the face while adduction refers to moving the eye to the inside of the face). There are three types of Duane syndrome. Duane syndrome 2 results in marked or complete limitation of adduction with minimal or no limitation of abduction. Duane syndrome is inherited in an autosomal dominant manner.
This laboratory performs Sanger sequencing of the CHN1 gene.