LOSS OF HETEROZYGOSITY ON CHROMOSOME-17 AND MUTATION OF THE P53 GENE IN RETINOBLASTOMA

Loss of heterozygosity (LOH) on chromosome 17 and mutations of the p53 gene were examined in 25 retinoblastomas (RB), consisting of three fa milial tumors, nine hereditary tumors without family history, 11 non-h ereditary tumors, one recurrent tumor and one lung-metastatic tumor. L OH on chromosome 17 was detected in only one of the 23 primary RB. No mutations of the p53 gene were detected in the primary tumors. A recur rent tumor showed LOH on the short arm region of chromosome 17. LOH on chromosome 17 and a point mutation of the p53 gene were also detected in a metastatic tumor. These results suggest that LOH on chromosome 1 7 and mutation of the p53 gene may not be associated with the developm ent of primary RB, but may play a role in the progression of RB.