Molecular genetics of myeloid leukemia: identification of the commonly
deleted segment of chromosome 20
D Roulston, R Espinosa , M Stoffel, GI Bell and MM Le Beau
Department of Medicine, University of Chicago Cancer Research Center, IL.
A deletion of the long arm of chromosome 20 [del(20q)] is a recurring
abnormality in malignant myeloid disorders. The occurrence of the del(20q)
in a broad spectrum of myeloid disorders suggests that the loss of genetic
material on 20q could provide a proliferative advantage to myeloid cells,
possibly through the loss of a tumor-suppressor gene. We have examined a
series of patients with the del(20q) using fluorescence in situ
hybridization (FISH) with unique sequence probes that map along the length
of 20q, and have delineated a segment that is deleted in 95% of all
patients examined (18 of 19). In addition, we have shown that the deletions
are interstitial rather than terminal. This region of deletion extends from
20q11.2 to q12, and is flanked by the RPN2 (proximal) and D20S17 loci
(distal). The SRC and ADA genes are located within the commonly deleted
segment. Our findings emphasize the importance of FISH and other molecular
mapping techniques in defining such a region. The delineation of a commonly
deleted segment in 20q11.2- q12 will facilitate the identification of
candidate tumor-suppressor genes on 20q.
Volume 82,
Issue 11,
pp. 3424-3429,
12/01/1993
Copyright © 1993 by The American Society of Hematology
