Duane Retraction Syndrome 2

Clinical Characteristics
Ocular Features: 

Duane retraction syndrome is a clinically and genetically heterogeneous condition with a highly variable phenotype.  It is a congenital and non-progressive strabismus syndrome.  Most cases occur sporadically but others are familial and about 30% of affected individuals have other congenital anomalies.  It is also seen as part of other syndromes such as Goldenhar (164210), and Wildervanck (314600).  In the absence of other anomalies, it is called isolated Duane syndrome.  Three heritable types with autosomal dominant familial patterns have also been defined.  Patients with type 2 discussed here are more likely to have an exotropia with a head turn toward the uninvolved side when only one eye is involved compared with Duane syndrome type 1 (126800) in which an esotropia with a head turn to the involved side is more common.  However, the clinical features are highly variable although intrafamilial differences may be less than those between families.

Sporadic cases are mostly unilateral while familial ones are more likely to be bilateral.  The essential features are globe retraction upon adduction with narrowing of the lid fissure and some limitation of abduction. Vertical deviation during adduction is sometimes seen.  Frank strabismus in primary position is evident in as many as 76% of individuals and a compensatory head turn is often adopted. Still, amblyopia occurs in at least 10% of individuals.  Females are affected more frequently than males.

At one point the syndrome was considered to be a myopathic disorder based on histologic changes in the lateral rectus but current thought based on MRI and neurohistologic studies favors a neuropathic etiology.  The abducens motor neurons and the sixth nerve may be absent or dysplastic.  Branches of the third nerve may also co-innervate the lateral and medial rectus muscles.  EMG studies have documented simultaneous activation of the two muscles which likely accounts for at least some of the globe retraction.  However, hypoplastic muscles, including the superior oblique, superior rectus, and levator, have also been visualized on MRI.

Systemic Features: 

A variety of skeletal and uroglogic anomalies have been found in association with the ocular findings of Duane syndrome but no consistent pattern has been documented.


Familial isolated Duane syndrome 2 individuals usually appear in an autosomal dominant pattern of inheritance caused by a mutation in CHN1 (2q31-q32.1).  The protein products appear to be involved in early neurological development and are critical to the formation of the cranial nerves that innervate the extraocular muscles.

Mutations in CHN1 are usually absent in nonfamilial cases of Duane syndrome.

For other forms of autosomal dominant Duane syndrome, see Duane Retraction Syndrome 1 (126800) and Duane Retraction Syndrome 3 (617041).

Pedigrees consistent with presumed autosomal recessive inheritance have also been reported but the responsible genes are unknown.

Features of Duane syndrome are also part of the Duane-Radial Ray Syndrome (607323).

Treatment Options: 

Various treatments can be useful, ranging from prisms for mild cases to muscle surgery for a severe head turn or vertical deviations.  Patients should be followed carefully in the first decade of life for the onset of amblyopia and appropriate treatment instituted.  Because of the variability in signs, each patient requires individualized treatment.

Article Title: 


Ferrario JE, Baskaran P, Clark C, Hendry A, Lerner O, Hintze M, Allen J, Chilton JK, Guthrie S. Axon guidance in the developing ocular motor system and Duane retraction syndrome depends on Semaphorin signaling via alpha2-chimaerin. Proc Natl Acad Sci U S A. 2012 Aug 21. [Epub ahead of print] PubMed PMID: 22912401.

PubMedID: 22912401

Miyake N, Andrews C, Fan W, He W, Chan WM, Engle EC. CHN1 mutations are not a common cause of sporadic Duane's retraction syndrome. Am J Med Genet A. 2010 Jan;152A(1):215-7. PubMed PMID: 20034095.

PubMedID: 20034095

Demer JL, Clark RA, Lim KH, Engle EC. Magnetic resonance imaging evidence for widespread orbital dysinnervation in dominant Duane's retraction syndrome linked to the DURS2 locus. Invest Ophthalmol Vis Sci. 2007 Jan;48(1):194-202. PubMed PMID: 17197533.

PubMedID: 17197533

Chung M, Stout JT, Borchert MS. Clinical diversity of hereditary Duane's retraction syndrome. Ophthalmology. 2000 Mar;107(3):500-3. PubMed PMID: 10711888.

PubMedID: 10711888

Kim JH, Hwang JM. Presence of the abducens nerve according to the type of Duane's retraction syndrome. Ophthalmology. 2005 Jan;112(1):109-13. PubMed PMID: 15629829.

PubMedID: 15629829