The disorder known as 22q11.2 deletion syndrome is caused by the deficiency or deletion of a tiny piece of chromosome 22. This deletion happens near the midsection of a chromosome located at q 11.2.
There are various estimates when it comes to the prevalence of the syndrome. In a study based in Sweden, the annual occurrence was at 14.1 for every 100,000 births. This is based on a study conducted by CDC or the Centers for Disease Control with about 6,000 subjects from different ethnic backgrounds.
This syndrome can affect many human body parts. The most common symptoms include defects of the heart (often present at birth); cleft palate and other defects of the palate; even facial defects (an example is a patient with 'crying face'). Other diseases could occur such as kidney disorders or abnormalities, seizures caused by low calcium levels in the blood (which is also known as hypocalcemia occurring in about 17-60% cases), and hearing loss. Most of the patients of this syndrome also acquire autoimmune diseases such as Grave's disease or rheumatoid arthritis. It is also possible to acquire skeletal disorders such as short stature or spinal bone abnormalities. Abnormalities on the patient's eyes can also occur: examples include ptosis, upper lid hooding, lower lid hooding, epicanthanl folds, and distichiasis. Other findings include embryotoxon, sclerocornea, corneal nerve isolation, deep iris crypts, small optic nerves and tilted discs. Children who are afflicted with this syndrome have delays on their growth and development. It is also possible that they will have learning disabilities, and worse, it could develop into mental illnesses like depression, bipolar disorder, anxiety and schizophrenia.
Patients with congenital heart defects caused by 22q11.2 deletion syndrome can be treated in the same manner as regular patients. Those with feeding complexities are given spoon placement modifications; acid blockade is used as a treatment for gastric reflux on the esophagus; postural therapy for those with postural problems; and prokinetic agents. Craniofacial teams can take care of abnormalities of the palate while MRA or magnetic resonance angiography may help in identifying risks during surgical procedures. Genetic counseling and pre-natal testing are also advisable. Genetic clinics are great sources of help and information among patients and their supportive families. These clinics often discuss the history, inheritance mode, treatment and the risks to all other members of the family. There are also many support groups that have been established to help the affected individuals and their families.