[New polymerase gene in pancytopenia (author's transl)]

Increasing evidence has accumulated that the direct assay of reverse transcriptase in human blood cells is of value in the diagnosis of leukaemia. The isolation and characterization of this enzyme has shown that it possesses remarkable similarities to the DNA-polymerase of the RNA-tumour virus of simian sarcoma. Hence, leukaemic cells in humans are thought to possess a virus-related gene, namely, reverse transcriptase. Various clinical reports have established the presence of this enzyme in blood cells, not only in the case of morphologically-proven malignant change, but also in cases classified as non-leukaemic from the morphological picture, such as acute leukaemia in remission and in the pre-leukaemic state. In confirmation and augmentation of earlier views we now report on the presence of reverse transcriptase in a patient with pancytopenia, who subsequently developed acute leukaemia i.e. isolation of the enzyme occurred in the pre-leukaemic state.