Some clinical aspects of human cytogenetics.

EXPECTATIONS of discoveries, relating chromosome aberrations in tumour cells to the type of growth, benign or malignant, have not often been justified. Cultures from most tumours have normal karyotypes and in leukemias, for example, the abnormalities found, except for the famous Philadelphia deletion in the chronic myeloid type, are not consistent or characteristic. Moreover, a mongol with leukaemia remains an ordinary trisomic mongol. However, a direct relationship between somatic disease and chromosomal aberration is sometimes demonstrable by investigating other types of problems which arise in clinical medicine. Four examples have been chosen.