Benedict W F, Srivatsan E S, Mark C, Banerjee A, Sparkes R S, Murphree A L
Cancer Res. 1987 Aug 1;47(15):4189-91.
Sixteen retinoblastomas were examined with chromosome 13 polymorphic probes to determine the frequency of homozygosity for the chromosome in the tumors. Each of the tumors had two cytogenetically normal appearing No. 13 chromosomes. Nontumorous cells from the same patients were heterozygous for the various polymorphic chromosome 13 probes used. At least partial homozygosity for a single chromosome 13 was observed in 75% of the tumors. These studies confirm and extend previous studies which suggest that homozygosity or hemizygosity at RBI occurs in the majority of retinoblastomas. We also demonstrate in an additional tumor that rapid clonal evolution from hemizygosity to homozygosity can occur in the tumor.
使用13号染色体多态性探针检测了16例视网膜母细胞瘤，以确定肿瘤中该染色体的纯合频率。每个肿瘤均有两条细胞遗传学上看似正常的13号染色体。同一患者的非肿瘤细胞对于所使用的各种13号染色体多态性探针是杂合的。在75%的肿瘤中观察到至少一条13号染色体存在部分纯合性。这些研究证实并扩展了先前的研究，这些研究表明大多数视网膜母细胞瘤中存在RBI基因的纯合性或半合子性。我们还在另一例肿瘤中证明，肿瘤中可发生从半合子性到纯合性的快速克隆进化。
