Cat Eye Syndrome
Also known as: CES, Schmid-Fraccaro Syndrome, Partial Trisomy 22, Tetrasomy 22pter-q11
Cat Eye Syndrome (CES) is a rare genetic disorder caused by a partial trisomy or tetrasomy of chromosome 22, specifically involving the 22pter-q11 region. It is characterized by a wide range of congenital malformations, most commonly affecting the eyes (coloboma), ears, heart, and kidneys. The severity of symptoms varies greatly among affected individuals.
Imagine your body has instructions to build itself, like a Lego set. Cat Eye Syndrome happens when there's an extra little piece of one of the instructions (chromosome 22). This extra piece can cause problems with how your eyes, ears, heart, and other body parts are built, making them a little different.
Signs & Symptoms
- Iris coloboma (key feature)
- Anal atresia with or without fistula
- Preauricular skin tags or pits
- Downslanting palpebral fissures
- Heart defects (e.g., total anomalous pulmonary venous return)
- Kidney abnormalities (e.g., renal agenesis, hydronephrosis)
- Skeletal abnormalities (e.g., scoliosis, vertebral anomalies)
- Mild to moderate intellectual disability
- Growth retardation
- Hearing loss
Treatment Options
Surgical correction of anal atresia
HIGHLY EFFECTIVESurgical repair of heart defects
HIGHLY EFFECTIVEManagement of kidney abnormalities
SUPPORTIVEHearing aids or cochlear implants for hearing loss
HIGHLY EFFECTIVESpecial education and developmental therapies for intellectual disability
SUPPORTIVECorrective lenses or surgery for vision problems
SUPPORTIVEDiagnosis
- Clinical evaluation
- Chromosome analysis (karyotyping) to detect partial trisomy/tetrasomy 22
- Fluorescence in situ hybridization (FISH) to confirm the presence of extra 22pter-q11 material
- Chromosomal microarray analysis (CMA)
- Echocardiogram to assess heart defects
- Renal ultrasound to assess kidney abnormalities
- Hearing test (audiometry)
- Ophthalmological examination
History
Cat Eye Syndrome was first described in the medical literature in the late 1960s. The term 'Cat Eye Syndrome' was coined due to the characteristic iris coloboma observed in many affected individuals. The underlying genetic cause, involving partial trisomy/tetrasomy of chromosome 22, was later identified through advancements in cytogenetic techniques.
Recent Breakthroughs
Identification of CECR1/ADA2 as a key gene in Cat Eye Syndrome
Research has highlighted the role of the CECR1/ADA2 gene, located in the critical region of chromosome 22q11, in the pathogenesis of Cat Eye Syndrome. Mutations in this gene have been linked to vasculopathy and inflammation, providing insights into the diverse clinical manifestations of the syndrome.