A disorder caused by a defect in chromosome 22.

DiGeorge syndrome is a chromosomal disorder that results in poor development of several bodily systems. Its features vary widely, even among members of the same family. Medical problems commonly associated with 22q11.2 deletion syndrome include heart defects, poor immune system function, a cleft palate, complications related to low levels of calcium in the blood, and delayed development with behavioral and emotional problems. The number and severity of symptoms associated with 22q11.2 deletion syndrome vary.

CAUSES

Each person has two copies of chromosome 22, one inherited from each parent. If a person has DiGeorge syndrome (22q11.2 deletion syndrome), one copy of chromosome 22 is missing a segment that includes an estimated 30 to 40 genes. Many of these genes haven’t been clearly identified and aren’t well-understood. The region of chromosome 22 that’s deleted is known as 22q11.2.

The deletion of genes from chromosome 22 usually occurs as a random event in the father’s sperm or in the mother’s egg, or it may occur early during fetal development. Rarely, deletion is an inherited condition passed to a child from a parent who also has deletions in chromosome 22 but may or may not have symptoms.

SYMPTOMS

• Heart murmur and bluish skin due to poor circulation of oxygen-rich blood (cyanosis) as a result of a heart defect
• Frequent infections
• Certain facial features, such as an underdeveloped chin, low-set ears, wide-set eyes or a narrow groove in the upper lip
• A gap in the roof of the mouth (cleft palate) or other problems with the palate
• Delayed growth
• Difficulty feeding, failure to gain weight or gastrointestinal problems
• Breathing problems
• Poor muscle tone
• Delayed development, such as delays in rolling over, sitting up or other infant milestones

• Delayed speech development or nasal-sounding speech
• Learning delays or disabilities
• Behavior problems

TREATMENT

• Although there is no cure for DiGeorge syndrome (22q11.2 deletion syndrome), treatments can usually correct critical problems, such as a heart defect or cleft palate. Other health issues and developmental, mental health or behavioral problems can be addressed or monitored as needed.
• Counseling
• Developmental therapy
• Behavioral modification techniques
• Surgical correction for cleft palate and heart defect