Cytogenetics

Abstract

The relationship between chromosome abnormalities and neoplasia has been the subject of investigation and speculation for many years. It was noted very early that mitotic irregularities were common in routine sections prepared from many human tumors, and these observations were extended by workers such as von Hansemann (1890) and Boveri (1914) to suggest a causal relationship between chromosome alterations and cancer. With the development of modern techniques of mammalian cytogenetics in the late 1950s (Hsu and Pomerat, 1953; Tjio and Levan, 1956; Moorhead et al., 1960), interest in chromosome studies of tumors was reawakened, and subsequently a wide variety of human and animal neoplasms were studied. This work has received additional impetus in the past few years from the introduction of “banding” methods that permit the identification of individual chromosomes and of alterations in smaller segments of chromosomes than was possible by previous techniques (Caspersson et al., 1968; Seabright, 1971). Although these newer methods have not yet been fully exploited, it must also be recognized that even with the banding procedures, there may still remain significant genetic alterations in neoplastic cells that are below the level of detection with the light microscope.