A COMMON DELETION IN 2 GAMMA-RAY INDUCED RAT PULMONARY TUMOR-CELL LINES

Subtraction hybridization was performed on normal WAG/Rij rat DNA with DNA from a syngeneic Ir-192 induced pulmonary tumor cell line L37. Th e residual DNA was amplified by means of sequence-independent PCR. Thi s procedure yielded a sequence, of which multiple copies are present i n normal rat DNA. In the tumor line L37 two restriction. fragments hyb ridizing with this repeat sequence are lacking. In another Ir-192 indu ced pulmorary tumor line, L33, one of these fragments was also lacking . This indicates a common deletion in the two tumor lines.