Marcus Gunn jaw winking associated with Duane's retraction syndrome.

: We report a case of an unusual association between Duane retraction syndrome and Marcus Gunn jaw-winking syndrome in the eye of a patient without other anomalies.: Clinical case. A four-year-old boy presented mild blepharoptosis of the left upper eyelid. The infant momentarily elevated the upper eyelid to a higher level by opening the mouth and thrusting the jaw to the right side. While attempting to abduct the left eye, there was no movement with the widening of the left palpebral fissure. Still, the normal movement of the right eye was consistent with the left rectus paralysis. Upon adduction of the left eye, the left palpebral aperture narrowed with retraction of the left eyeball.: The patient underwent an elevator resection on the affected side, achieving a satisfactory functional and cosmetic result. He has a normal life without concerns regarding his vision or appearance.: We present a patient with DRS and MGJWS in the same eye. DRS has an absence of the abducens nerve and an aberrant innervation of the lateral rectus by branches originating from the inferior division of the oculomotor nerve. MGJWS presents connections of the trigeminal nerve to muscles of mastication and superior division of the oculomotor nerve controlling the levator palpebrae superioris. Embryologically, the motor branches of the trigeminal and oculomotor nuclei are close, explaining the possible abnormal connection. Some genes illustrate the absence of the abducens nerve and the overexpression of the trigeminal neurons, relating to both syndromes.