Cat Eye Syndrome

Schmid-Fraccaro Syndrome

What is Cat Eye Syndrome?

Cat Eye Syndrome is an abnormality in the ocular region in which the pupil appears to dip down. It is commonly known as Cat Eye Syndrome because many appear to have the pupil shape of a cat (Zoll 1).

The Cause

This rare disorder is caused by a mutation in X chromosome 22. When the short arm (p) and a piece of the long arm (q) are present three or four times rather than twice, this causes Cat Eye Syndrome (Zoll 2).


Who is at Risk?

As far as doctors have observed, this disorder is very sporadic. Many cases have shown just an error in the dividing sex cells of the parents, but there have been cases in which a parent has mild features of this disorder and their child was affected (Zoll 2). Cat Eye Syndrome is dominant, but does not act the same as many dominant traits. This is because it comes from an abnormal copy of X chromosome 22 (Brands 2). But it is possible for anyone to be affected. These people may have children in the future but it is unknown if their children will be affected as research is not clear on a cause or any cure or treatment other than surgery (Zoll 13).


It is possible for this disorder to be discovered prenatally. It is possible for an ultrasound to reveal a possibility of a disorder, but the most reliable would be an amniocentesis which requires the doctor to extract some fluid surrounding the fetus and then studied to find any disorders in chromosome structure (Reeser, Donnenfield, Miller, Sellinger, Emanuel, Driscoll 1).


The only treatment available is to get surgery for the anus and heart, as well as the eyes to help improve vision even in the slightest. Luckily, those with this syndrome don't have a reduced life expectancy because of such heart problems. Those affected by this do not need any more medical assistance other than these surgeries (Kulgar 11).