ASSIGNMENT OF THE HUMAN ENDOGLIN GENE (END) TO 9Q34-]QTER

Endoglin is a homodimeric membrane glycoprotein primarily associated w ith human vascular endothelium. It is also found on bone marrow proery throblasts. activated monocytes and on lymphoblasts in childhood leuke mia. Endoglin has recently been described as a component of the transf orming growth factor-beta (TGF-beta) receptor system as it can bind TG F-beta1 with high affinity. We now report on the localization of the h uman endoglin gene (END) to human chromosome 9, by Southern blot analy sis of Bg/II fragments of DNA from human-hamster somatic cell hybrids. This chromosomal localization was confirmed by fluorescent in situ hy bridization coupled with Distamicin A (DA)/4',6-diamidino-2-phenylindo le (DAPI) banding on human chromosomes. The regional localization was assigned to 9q34 --> qter by GTG-banding (G-banding by trypsin using G iemsa stain), indicating a telomeric position with respect to the Phil adelphia breakpoint.