[Localization of 8q24 break-point of Burkitt lymphoma in Japan : relationship to EBV status].

It has been reported that the break point of 8q24 in t (8; 14) (q24; q32) is located far up-stream from c-myc gene locus in endemic EBV (Epstein-Barr virus)-positive BL, while the break-point is located close to the 1st intron of c-myc gene in sporadic EBV-negative BL. Considering that no statistical analysis is available regarding BL in Japan, the break-point of chromosome No.8 was investigated in 13 BL/L3 cell lines (having t(8; 14)) and 4 fresh samples derived from Japanese patients, including 3 EBV-positive BL cell lines, by using long-distance PCR. In this PCR, one primer was set in the 2nd intron of the c-myc gene, and the other primer in Ig constant region gene, mu, gamma, alpha and epsilon. This long distance PCR can cover up to 30 kb. Thus, this PCR does'nt generate product, if the 8q24 break-point is located far up-stream (more than 50 kb) fom c-myc gene. In 2 of the 3 t (8; 14) EBV-positive BL lines, no product was generated in two lines(N831 and Middle 91), while a product was synthesized in one line(Akata), indicating that the 8q24 break-point is near the c-myc gene in Akata. In all the other BL/L3 lines, a product was synthesized. A larger number of BL cases are necessary to investigate in order to know which 8q24 break-point pattern is exhibited by EBV-positive BL in Japan, while this method is suitable for testing a large number of case materials.