DiGeorge syndrome is a complex birth defect. In most cases there is a chromosomal defect on chromosome 22. DiGeorge consists of a particular group of symptoms frequently occurring together, including the following:
hypoparathyroidism (underactive parathyroid gland), which results in hypocalcemia (low blood calcium levels)
hypoplastic (underdeveloped) thymus or absent thymus, which results in problems in the immune system
conotruncal heart defects (i.e., tetralogy of Fallot, interrupted aortic arch, ventricular septal defects, vascular rings)
cleft lip and/or palate
In the 1980s, the technology was developed to identify underlying chromosome defects of three similar syndromes. It was determined that over 90 percent of all patients with features of DiGeorge, Shprintzen, and velo-cardio-facial syndromes had a chromosome deletion in the region of 22q11. In other words, this was the same syndrome, but because several different researchers in different areas of expertise had described it, the syndrome carried multiple names. Many physicians and researchers today use the term 22q11 deletion syndrome because it describes the underlying chromosome problem, or velo-cardio-facial syndrome (VCFS) because it describes the main body systems involved.
Statistically, patients with DiGeorge have the following:
69 percent have palatal abnormalities (such as cleft lip and/or palate)
30 percent have feeding difficulties
80 percent have conotruncal heart defects (i.e., tetralogy of Fallot, interrupted aortic arch, ventricular septal defects, vascular rings)
40 percent have hearing loss or abnormal ear exams
30 percent have genitourinary anomalies (absent or malformed kidney)
60 percent have hypocalcemia (low blood calcium levels)
40 percent have microcephaly (small head)
40 percent have mental retardation (usually borderline to mild)
IQs are generally in the 70 to 90 range
33 percent of adults have psychiatric disorders (i.e., schizophrenia, bipolar disorder)
2 percent have severe immunologic dysfunction (an immune system which does not work properly due to abnormal T-cells, causing frequent infections)
Approximately 10 percent of individuals who have the features velo-cardio-facial syndrome (VCFS) do not have a deletion in the chromosome 22q11 region. Other chromosome defects have been associated with these features, as have maternal diabetes, fetal alcohol syndrome, and prenatal exposure to Accutane® (a medication for cystic acne).
hypoparathyroidism (underactive parathyroid gland), which results in hypocalcemia (low blood calcium levels)
hypoplastic (underdeveloped) thymus or absent thymus, which results in problems in the immune system
conotruncal heart defects (i.e., tetralogy of Fallot, interrupted aortic arch, ventricular septal defects, vascular rings)
cleft lip and/or palate
In the 1980s, the technology was developed to identify underlying chromosome defects of three similar syndromes. It was determined that over 90 percent of all patients with features of DiGeorge, Shprintzen, and velo-cardio-facial syndromes had a chromosome deletion in the region of 22q11. In other words, this was the same syndrome, but because several different researchers in different areas of expertise had described it, the syndrome carried multiple names. Many physicians and researchers today use the term 22q11 deletion syndrome because it describes the underlying chromosome problem, or velo-cardio-facial syndrome (VCFS) because it describes the main body systems involved.
Statistically, patients with DiGeorge have the following:
69 percent have palatal abnormalities (such as cleft lip and/or palate)
30 percent have feeding difficulties
80 percent have conotruncal heart defects (i.e., tetralogy of Fallot, interrupted aortic arch, ventricular septal defects, vascular rings)
40 percent have hearing loss or abnormal ear exams
30 percent have genitourinary anomalies (absent or malformed kidney)
60 percent have hypocalcemia (low blood calcium levels)
40 percent have microcephaly (small head)
40 percent have mental retardation (usually borderline to mild)
IQs are generally in the 70 to 90 range
33 percent of adults have psychiatric disorders (i.e., schizophrenia, bipolar disorder)
2 percent have severe immunologic dysfunction (an immune system which does not work properly due to abnormal T-cells, causing frequent infections)
Approximately 10 percent of individuals who have the features velo-cardio-facial syndrome (VCFS) do not have a deletion in the chromosome 22q11 region. Other chromosome defects have been associated with these features, as have maternal diabetes, fetal alcohol syndrome, and prenatal exposure to Accutane® (a medication for cystic acne).