Cat Eye Syndrome Awareness Day Date in the current year: March 22, 2026

Most cells in our bodies have two copies of each chromosome, one inherited from the mother and the other from the father. However, some genetic conditions are characterized by the presence of an extra full or partial copy, or even several copies, of a particular chromosome. Cat eye syndrome (CES), also known as Schmid-Fraccaro syndrome, is one of these conditions.

Cat eye syndrome is caused by an extra chromosome consisting of some genetic material from chromosome 22, specifically the entire short arm and a small section of the long arm. Individuals with the syndrome may have one or, more commonly, two copies of the extra chromosome, in addition to the two regular copies of chromosome 22.

The syndrome is named for its most recognizable symptom, vertical iris coloboma. A coloboma is a hole in the iris that makes the eye look cat-like. However, approximately half of patients with cat eye syndrome do not have colobomas. In addition to coloboma, cat eye syndrome has many other signs and symptoms, such as:

• Anal abnormalities, most commonly anal atresia or stenosis
• Ear anomalies, such as small or malformed ears
• Preauricular skin tags or pits near the ears
• Congenital heart defects
• Kidney abnormalities or urinary tract malformations
• Skeletal abnormalities, including scoliosis and other spinal defects
• Growth delay or short stature
• Down-slanting palpebral fissures (eye openings)
• Cleft palate
• Micrognathia (small jaw)
• Hernias
• Biliary atresia (blocked or underdeveloped bile ducts)
• Mild to moderate intellectual disability in about 30% of patients

Not all patients experience all symptoms, and the severity of symptoms can vary greatly from patient to patient. Some individuals have only mild features that don’t significantly impact their lives, while others have multiple congenital abnormalities.

The long-term prognosis and life expectancy depend on the symptoms and their severity. Those with mild manifestations have a normal life expectancy and require minimal treatment. Those with significant congenital abnormalities, however, may require multiple surgeries and have a shorter than normal life expectancy.

Like most rare genetic conditions, CES does not have a cure. Management focuses on addressing specific symptoms and may include surgery for congenital defects, ophthalmological care for coloboma, speech therapy, occupational therapy, educational support for intellectual disability, and more.

Cat Eye Syndrome Awareness Day was launched to educate the public about this rare genetic condition, support patients and their families, and highlight the importance of improving access to medical care and conducting further research on the condition. You can participate by learning more about CES, donating to an organization that supports patients or funds research, and spreading the word on social media using the hashtags #CESAwarenessDay and #CatEyeSyndromeAwarenessDay.