Leukaemia cytogenetics / H. Jackson Woodliff.

  • Woodliff, H. Jackson.
Date:
1971
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Leukaemia cytogenetics / H. Jackson Woodliff. Source: Wellcome Collection.

    79/168 (page 63)
    CHRONIC GRANULOCYTIC LEUKAEMIA 63 relatively low positivity in some early cases suggests that two mye¬ loid clones may exist in the bone marrow, one with a normal karyotype and the other Ph positive. Support for this view is provided by Whang-Peng et al. (1968) some of whose patients had appreciable numbers of negative bone marrow cells. There is now ample evidence that the Ph chromosome is present in megakaryocytes and normoblasts as well as in myelocytes and therefore probably in the myeloid stem cell (Clein and Flemans, 1966; Fialkow et al., 1969; Frei et al, 1964; Hammouda et al., 1964; Rastrick et ah, 1968; Rastrick, 1969; Tough et al., 1963; Trujillo and Ohno, 1963; Whang-Peng et al, 1968ö and b). It has not been demonstrated in fibroblasts growing from skin and other tissues including the bone marrow (Baikie et al, 1960; Baikie et al, 1969; Biscatti and Vaccaro, 1965; Court Brown and Tough, 1963; Engel et al, 1965è; Levan eia/., 1963; Tough а/., 1961 and personal observations). Negative cells in the bone marrow may be non-leukaemic myeloid cells or occasionally cells of other types, such as lymphoblasts and osteoblasts. The Ph chromosome occurs in 0 to 100 per cent of cells cultured from the blood of patients with chronic granulocytic leukaemia. Negative findings reflect the state of remission where no primitive myeloid cells are present in the blood (Jung et al, 1963). The Ph chromosome has been found in splenic cells (Spiers and Baikie, \9в5Ь) but not in cells obtained from lymph nodes (Whang et al, 1963a and b). Origin of the Ph Chromosome The Ph chromosome is not present in the zygote and probably develops in one or more myeloid precursor cells some years before the clinical onset of chronic granulocytic leukaemia: it has been found in the early and asymptomatic phases of the disease on several occasions (Buxton et al, 1966; Woodlifif, 1969Z?). In favour of it being an acquired rather than an inherited defect is the fact that it is present only in myeloid cells, that it has not been found in monozygotic twins of six patients in chronic granu¬ locytic leukaemia (Table VII) and that it is not usually found in the cells of children born of parents with the disorder. Baikie et al. (1969) found the Ph chromosome in the bone marrow cells of a patient with chronic granulocytic leukaemia whose mother had died of the same disease but it was not identified in cultures of