When a small section from the middle of Chromosome 22 is missing, DiGeorge Syndrome occurs. The disorder happens in one of 4,000 pregnancies. DiGeorge Syndrome was discovered in 1968 by  Angelo DiGeorge.

When the middle of Chromosome 22 is missing, five distinct symptoms occur in the body. Doctors and researchers have given the name CATCH-22 to the symptoms. C – Cardiac Abnormalities. A – Abnormal facies. T – Thymic aplasia. C – Cleft palate. H – Hypocalcemia. The 22 is added as a reminder that the 22nd chromosome is responsible for the condition.

While DiGeorge Syndrome can be passed from parent to child, only about 10% of cases are attributed to a parent having a defect of chromosome 22. The remaining cases are characterized as being de novo or new to the family of genes. There is a 50 / 50 chance a parent with the disorder will pass the trait onto children.