Single cell detection of inherited retinoblastoma predisposition

Retinoblastoma susceptibility is an autosomal dominantly inherited cancer predisposition which also confers a life-long increased risk for various non-ocular malignancies. We developed a protocol for single cell detection of this disorder which enables its preimplantation genetic diagnosis as an alternative to prenatal diagnosis with attendant pregnancy termination. The presented method detects the underlying mutation of the disease, a linked intragenic polymorphism (p88PR0.6) and an independent marker (D21S1411) for genetic fingerprinting allowing detection of contamination. The strategy is based on the combination of nested triplex polymerase chain reaction, single strand conformation polymorphism analysis by conventional polyacrylamide gel electrophoresis and fragment size determination with automated laser fluorescence.