Researchers also discovered the syndrome's genetic basis: a rearrangement of DNA called "microduplication." When microduplication occurs, DNA segments are repeated and this causes a surplus of genes. Microduplication is a little-studied mechanism underlying the origin of human diseases, and Mayo Clinic researchers are in the forefront of scientists producing evidence for its impact. Their work is made possible by the February 2001 completion of the federal Human Genome Project, the mapping of all the major genes in the human body. It has produced a database that describes the DNA sequences of the entire human complement of genes, which is estimated to be around 30,000 genes. The Mayo Clinic research, "Microduplication 22q11.2: An Emerging Syndrome," appears in the November American Journal of Human Genetics (73:1027-40) (http://www.ajhg.org/AJHG/journal).
Symptoms
Specific symptoms of this syndrome may include slightly misshapen faces and unusually widely spaced eyes, eyebrows placed higher than usual, and long, narrow faces, with irregularly shaped ears. Some patients have impaired hearing and speech, malfunctioning spleen and thymus gland, or heart defects. Other symptoms: faulty immune function and degrees of mental impairment.
The Significance of the Mayo Clinic Research
The work is important from the perspectives of genetic counseling, patient care and the history of medicine. The risk of inheriting this syndrome is 50 percent for a child with one parent affected by it and it's highly likely that it runs in families. "This means it could make it a significant health concern," says Syed Jalal, Ph.D., a me
'"/>
4-Nov-2003