Localization of the gene responsible for familial benign polycythemia to chromosome 11q23

Familial benign polycythemia (FBP) (OMIM 263400) is a rare autosomal recess ive condition characterized by erythrocytosis, normal leukocyte and platele t counts, normal uric acid level, and usually increased erythropoietin prod uction. There is a high incidence of this disorder in Chuvashia (Russian Fe deration), probably due to a founder effect. In an attempt to locate the ge ne responsible for this disorder, we have carried out linkage studies in 12 Chuvash families, with 35 affected and 32 unaffected members. Linkage to t he erythropoietin and erythropoietin receptor loci was excluded, and the FB P gene was assigned to the region of chromosome 11q23 between D11S4142 and D11S1356, with a maximal lod score of 6.61.