Analysis of chromosome 6 deletions in lymphoid malignancies provides evidence for a region of minimal deletion within a 2-megabase segment of 6q21.

Fluorescence in situ hybridization has been used to define deletion breakpoints within chromosome bands 6q16-21 in cases of lymphoid malignancy. Previous evidence suggested that the region might contain a tumour-suppressor gene. Six yeast artificial chromosome probes, each selected using a single marker, were localized to 6q16-21 and the following order was confirmed; D6S330-D6S283-D6S301-D6S447-D6S246-FYN+ ++. Of 32 cases of lymphoid malignancy, 30 showed deletion of D6S246 and, in the two cases in which D6S246 was retained, the adjacent marker, D6S447, was deleted. These observations imply that a region of minimal deletion is located within a 2-megabase segment of 6q21, between D6S447 and D6S246, providing a candidate region for the location of a tumour-suppressor gene.