Inheritance: X-linked, affecting primarily males
Chromosome: Xq13
Gene affected: ATRX (transcriptional regulator)
Clinical features:
(1) facial dysmorphic features
(1a) small head circumference
(1b) upswept frontal hair
(1c) telecanthus or ocular hypertelorism
(1d) small triangular nose with retracted columella
(1e) tented upper lip
(1f) open mouth expression with or without tongue protrusion
(1g) drooling
(1h) everted lower lip
(1i) strabismus
(2) severe developmental delay in speech and walking
(3) mental retardation
(4) hypotonia
(5) abnormal genitalia (cryptorchidism, hypospadias, ambiguous, female genitalia, other)
(6) short stature
(7) various skeletal anomalies (kyphosis, scoliosis, pectus carinatum, brachydactyly, clinodactyly, tapered digits, foot deformities, etc)
(8) joint contractures
(9) variable seizures
(10) gastroesophageal reflux with or without aspiration pneumonia
(11) gastrointestinal pseudo-obstruction
(12) constipation
(13) poor feeding
(14) variable microcytic anemia with alpha thalassemia and hemoglobin H
(15) variable asplenia
(16) variable malformations affecting the heart and other organs
