Flow Cytometric Testing for Syndromes with Chromosomal Instability, Aplastic Anemia and Related Hematological Disorders

Abstract

Traditionally, the evaluation of metaphase chromosomes for breaks and rearrangements has evolved as the diagnostic tool for the identification or confirmation of syndromes associated with chromosomal instability. However, many of these syndromes exhibit poor cell proliferation, and often metaphases are not abundant. Moreover, the analysis of metaphases at the microscope is cumbersome and time-consuming, and only limited numbers (50–100) can be scored. We have developed a simple, fast, and, at least in part, automated procedure which complements or, in certain cases, may substitute microscopic analyses with regards to accuracy and reproducibility (Rabinovitch et al 1988, Kubbies et al 1989, Poot et al 1994). This alternative assay using flow cytometry employs cell cycle analysis of peripheral blood lymphocytes activated in vitro (Figure 1). The cell cycle test has been successfully applied to the diagnosis of Fanconi anemia (FA) (Kubbies et al 1985, Seyschab et al 1993, Seyschab et al 1995), severe forms of non-Fanconi type aplastic anemia (non-FA) and related hematological disorders (Tschampa et al, submitted), ataxia telangiectasia (A-T) (Seyschab et al 1992), as well as the Nijmegen breakage syndrome (NBS) (Barbi et al 1991).