trisomy 22

Trisomy 22 is frequently seen in first trimester miscarriages but is extremely rare in life-borns. Trisomy 22 is commonly found among spontaneous abortions, second in frequency of occurrence only to trisomy 16. Most earlier reports of surviving trisomy 22 cases in the literature are thought to represent the product of unbalanced 11;22 translocations or the result of undetected mosaicism, since this condition is thought to manifest early embryonic or fetal lethality.

Types

 non-mosaic trisomy 22
 unbalanced 11;22 translocations
 mosaic trisomy 22

Synopsis

 intra-uterine growth retardation (IUGR)

• hypotrophism
• bilateral pterygium colli

 craniofacial anomalies

• microcephaly
• brachycephaly
• arhinincephaly
• holoprosencephaly
• microphthalmia
• small palpebral fissures
• prominent eyes
• colobomata
• cleft palate/cleft lip

 facial dysmorphism

• thin upper lip
• cranial / facial assymetry
• frontal bossing
• depressed superciliary region
• occiputal anomaly
• sparse hair
• hypertelorism
• downslanting eyes
• epicanthal folds
• broad flat nasal bridge and broad nose, flat nose
• ocular hypertelorism
• long philtrum
• webbed neck
• micrognathia
• hypertelorism
• frontal bossing
• bulbous nose
• antimongoloid slant of the palpebral fissures
• strabismus
• long philtrum
• large rotated protruding low-set auricles
• Goldenhar syndrome (facioauriculo-vertebral dysplasia)
• low set ears
• malformed ears
• ear pits / ear tags
• microtia
• variable cleft palate
• webbed neck

 pectus excavatum
 abnormal dermatoglyphics
 absent gall bladder

 cardiovascular malformations

• ventricular septal defect
• Fallot pentalogy
• atresia of pulmonary valve
• dextroposition of the aorta
• hypertrophy of the right atrum and ventricle
• ventricular Septal defect
• great interatrial septal defect
• malformations of great vessels
• persistent left cardinal vein
• absent right umbilical artery
• nuchal skinfold thickness increase
• thyroid isthmus agenesis
• single umbilical artery

 cerebrospinal anomalies

• absence of corpus callosum
• limbal and epibulbar complex choristoma
• microcephaly

 diaphragmatic hernia

 limb anomalies

• hypoplastic nails
• clinodactyly
• radial anomaly
• hypoplastic digits
• simian crease
• bracydactyly
• small hands
• hallux valgus
• clubbed feet
• limited range of motion
• rocker bottom feet

 anomalous external genitalia

• hypotonia hypospadias
• hydrocephaly small phallus

 anorectal malformations
 renal malformations

 anomalous internal genetalia

 left hemifacial microsomia
 narrow chest
 intrauterine dystrophy
 hypoplastic nipples

 hypoplastic scrotum
 strabismus
 undescended testes
 antimongoloid palpebral fissures
 anal stenosis / atresia
 short wide neck
 distal limb hypoplasia
 no fingertip pattern
 persistant left superior vena cava
 dry, thin wrinkled skin
 genital malformation or hypoplasia
 small dysplasic kidneys
 bilateral cleft lip and palate
 hypoplastic lungs, pancreas and adrenals
 low set ears
 bilateral absence of olfactory bulbs and tracts
 excess nuchal skin
 incomplete descent of the cecum
 proximally placed or fingerlike thumbs
 long fingers
 Pierre Robin Syndrome
 tonic-clonic seizures
 contracted pelvis
 imperforate anus with anovulvar fistula
 hypoplastic distal digits
 thumb anomalies

 intersex (sexual ambiguity)

• external male organs but rudimentary female internal organs (8092876)

 uveal colobomas

 cutis laxa on arms and hands
 unilateral transverse palmar crease
 elbow joints contracted in felxion

 hypoplasia of the bilobate lungs
 multiple hypoplasia of the diaphragm

 lien pendulans

 kyphosis

 sacral dimple

 digestive anomalies

• malrotation of gut
• anorectal anomalies

 renal anomalies

• bilateral renal agenesis (7625758)

 lymphedema

Mosaic trisomy 22

 intrauterine growth retardation
 mental retardation
 failure to thrive, short stature
 craniofacial asymmetry
 ocular anomalies (15255116)

• ptosis
• double elevator palsy
• high myopia
• choroidal coloboma involving the macula

 terminal transverse limb reduction defect

• absent hand

 congenital cardiac defect
 facial dysmorphism
 skin pigmentary anomalies
 intersex

• XX intersex (8092876)

Trisomy 22q13-qter (Partial duplication 22, partial trisomy 22)

 pre- and postnatal growth retardation
 hypertelorism
 bilateral cleft lip and palate
 peripheral pulmonary stenosis

References

 Bacino CA, Schreck R, Fischel-Ghodsian N, Pepkowitz S, Prezant TR, Graham JM Jr. Clinical and molecular studies in full trisomy 22: further delineation of the phenotype and review of the literature. Am J Med Genet. 1995 May 8;56(4):359-65. PMID: 7604844