Schinzel phocomelia syndrome is characterized by limb/pelvis hypoplasia/aplasia: specifically, intercalary limb deficiencies and absent or hypoplastic pelvic bones. The phenotype is similar to that described in a related multiple malformation syndrome known as Al-Awadi/Raas-Rothschild syndrome.
The Al-Awadi/Raas-Rothschild/Schinzel phocomelia syndrome is caused by mutation in the WNT7A gene
Autosomal recessive disease.
Synopsis
large parietooccipital skull defects without meningocele
encephalocele
brain malformations
quadrilateral intercalary limb deficiencies
preaxial toe polydactyly
absent pelvis
skull defects
microtia
telecanthus
micropenis
cryptorchidism
renal cysts
stenosis of the colon
cleft alveolar ridge
46,XY karyotype
autosomal recessive inheritance presumed
severe pelvic anomalies
skull anomalies
Short stature, disproportionate
Asymmetric facies
Long facies
Long ears
Dysplastic ears
Low-set ears
Epicanthal folds
Broad nasal bridge
High palate
Narrow palate
Short neck
Broad neck
Barrel-shaped chest
Prominent sternum
Pectus carinatum
Pseudoarthrosis of clavicle
Broad clavicles
Broad ribs
Hypoplastic nipples
Anteriorly displaced genitalia
Hypospadias
Hypoplastic scrotum
External genitalia, female
Anteriorly displaced genitalia
Internal genitalia, male
Cryptorchidism
Absent uterus
Poorly ossified calvarium
Hemivertebrae
Hip dislocation
Hypoplastic iliac bone
Aplastic pubic bones
Elbow flexion contractures
Shortened forearm
Short, bowed radii
Aplastic ulnae
Humeroradial synostosis
Short, bowed femur
Aplastic fibulae
Aplastic tibiae
Slender tibiae
Aplastic carpal bone
Mobile wrist
Aplastic/hypoplastic metacarpals
Aplastic/hypoplastic phalanges
Ectrodactyly
Oligodactyly
Aplastic/hypoplastic tarsals
Aplastic/hypoplastic metatarsals
Aplastic/hypoplastic phalanges
Hypoplastic feet
Oligodactyly
Pilonidal sinus
Anonychia
Occipital meningocele
Etiology
germline mutation in the WNT7A gene (MIM.601570)
- allelic to Fuhrmann syndrome (MIM.228930) (fibular aplasia or hypoplasia, femoral bowing, and poly-, syn-, and oligodactyly)
Differentiating diagnosis
other multiple malformation syndromes with intercalary limb defects
- thalidomide embryopathy
- Roberts-SC phocomelia
References
Olney RS, Hoyme HE, Roche F, Ferguson K, Hintz S, Madan A. Limb/pelvis hypoplasia/aplasia with skull defect (Schinzel phocomelia): distinctive features and prenatal detection. Am J Med Genet. 2001 Nov 1;103(4):295-301. PMID: 11746009