Chromosome: 20q13.2
Gene: SALL4 (Sal-like protein 4)
Inheritance: autosomal dominant
Key features:
(1) radial ray anomalies
(2) urinary tract abnormalities affecting the kidney or bladder
(3) ocular coloboma, ptosis and/or Duane anomaly
Radial ray anomaly may involve one or more of the following:
(1) thenar hypoplasia
(2) hypoplasia or aplasia of the thumbs
(3) hypoplasia or aplasia of the radii
(4) shortening and radial deviation of the forearm
(5) triphalangeal thumbs
(6) preaxial polydactyly with duplicaton of the thumb
Urinary tract abnormalities may involve one or more of the following:
(1) malrotation
(2) ectopia
(3) hoarseshoe kidney
(4) hypoplasia
(5) vesico-ureteral reflux
(6) bladder diverticula
Duane anomaly consists of:
(1) unilateral or bilateral limitation in eye abduction secondary to abnormal innervation of the lateral rectus muscle
(2) retraction of the globe
(3) narrowing of the palpebral fissue on adduction
(4) absence of cranial nerve VI (abducens nucleus and nerve) with a branch of cranial nerve III (oculomotor nerve) innervating the lateral rectus muscle
The patient may also have other features seen in SALL4-related disorders (see below).
Differences from the Duane-Radial Ray syndrome include: coloboma and the urinary tract abnormalities
