A physical linkage group in human chromosome band 11q23 covering a region implicated in leukocyte neoplasia.

Six genes on human chromosome band 11q23 have been linked by pulse-field gel electrophoretic analysis with the order cen-CD3E-CD3D-CD3G-PBGD-CBL2-THY1-qter. The corresponding long-range restriction map covers 1.8 Mb, the telomeric half of which (PBGD-CBL2-THY1) is localized to subband 11q23.3. Four genes (CD3E, CD3D, CD3G, and PBGD) can be positioned precisely, and with known transcriptional orientation, with respect to rare-cutter restriction sites. The linkage group covers a region implicated in leukocyte malignancy: several nonrandom neoplasia-associated translocation chromosomes have breakpoints which separate the CD3 genes from PBGD, CBL2, and THY1. Thus, we are able to localize such breakpoints, and consequently any affected candidate genes, to the 750 kb between CD3G and PBGD.