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A syndrome characterized by marked limitation of abduction of the eye, variable limitation of adduction and retraction of the globe, and narrowing of the palpebral fissure on attempted adduction. The condition is caused by aberrant innervation of the lateral rectus by fibers of the oculomotor nerve. There are three subtypes: type 1 (associated with loss of abduction), type 2 (associated with loss of adduction), and type 3 (loss of abduction and adduction). Two loci for Duane retraction syndrome have been located, one at chromosome 8q13 (DURS1) and another at chromosome 2q31 (DURS2). It is usually caused by congenital hypoplasia of the abducens nerve or nucleus, but may rarely represent an acquired syndrome. (Adams et al., Principles of Neurology, 6th ed, p271; Miller et al., Clinical Neuro-Ophthalmology, 4th ed, p691)