Mouse p73 gene maps to the distal part of chromosome 4 and might be involved in the progression of gamma-radiation-induced T-cell lymphomas

We have isolated and sequenced a DNA fragment of about 12 kb that comprises exons 5-14 of the mouse p73 gene. We have identified four polymorphic mark ers, and one of them has been used to genetically map p73 to the distal par t of chromosome 4. Previously, we have reported that gamma-radiation-induce d T-cell lymphomas undergo frequent loss of heterozygosity around marker D3 Mit205b at the distal part of chromosome 4. Based on this, we have performe d loss of heterozygosity analysis in a set of T-cell lymphomas. and we have found allelic losses of p73 in 32.6% (16 of 49) of the tumors analyzed. In terestingly, allelic losses occur concurrently at both p73 and D4Mit205b, t hus suggesting that p73 could be specifically inactivated in radiation-indu ced T-cell lymphomas.