Horwitz's Australian colleagues had described a family with a similarly inherited blood disorder. Eighteen years later, after rifling through many candidate genes, the researchers on both continents were relieved finally to have hit upon the mutated gene responsible for the leukemia that affect these families. They have gone on to identify abnormal GATA2 genes in more than 20 families and individuals.
"It's likely that this inherited error is more common than we had thought," the researchers noted. In some families with a GATA2 mutation, the over-riding concern has been leukemia, while others suffer dangerous infections from bacteria, viruses and fungi because of a lack of white blood cells to fight off germs.
The lab of Dr. Dennis Hickstein, formerly of the UW School of Medicine and the Puget Sound Veterans Affairs Health System and now at the National Institute of Health, in collaboration with NIH colleague Dr. Steven Holland, associated the mutation with mycobacteria infections. Those results were reported in separate study appearing in the journal Blood.
Another paper appearing Sept. 4 in Nature Genetics from a London group found similar mutations of GATA2 in leukemia patients with lymphedema and, in some cases, deafnesss. By blocking the vessels that drain fluid from the body's tissues, lympedema causes swelling of the arms or legs.
Ongoing work in Seattle and Adelaide has identified a congenital syndrome associated with developmental delay and a risk of myelodysplasia. This syndrome results from chromosomal loss of GATA2 and adjacent genes.
Comparable GATA2 mutations also have been found in people with the more common, non-inherited leukemias.
Scientists are trying to figure out why apparently similar gene mutations i
|Contact: Leila Gray|
University of Washington