The molecular genetics of retinoblastoma and Wilms' tumor

Retinoblastoma and Wilms' tumor in children are sometimes associated with small constitutional chromosome deletions on chromosomes 13 and 11, respectively. This finding has highlighted regions of the human genome which are potentially important in the predisposition to the development of cancer. By using techniques in molecular biology, it is possible to isolate DNA sequences from specific chromosomes. Then, by using either a panel of somatic cell hybrids containing different overlapping deletions or in situ hybridization, it is possible to assign these DNA sequences to regions of particular chromosomes. DNA sequences isolated from within the frequently deleted regions will prove useful not only to improve understanding of the basic mechanism underlying cancer predisposition, but also to possibly allow prenatal diagnosis for those at risk.