Chromosome Instability Syndromes

Chromosomal instability syndromes are a group of inherited disorders associated with chromosomal instability and breakage either spontaneously or in response to DNA damaging agents. The majority of these syndromes are significant because they have associations with variable degrees of immunodeficiency, infectious disease, and the risk of developing certain types of malignancies. The following chromosomal instability syndromes are rare but well described. The current review will focus on the following syndromes. 1. Ataxia telangiectasia (AT) 2. Bloom syndrome (BS) 3. Fanconi anemia (FA) 4. Nijmegen breakage syndrome (NBS). Other rare syndromes include ataxia telangiectasia-like disorder, immunodeficiency/centromeric instability/facial anomalies syndrome, Cockayne syndromes, trichothiodystrophy, xeroderma pigmentosum, DNA ligase I deficiency, PMS2 deficiency, and DNA recombinase repair defects (DNA-PKcs, Artemis, DNA ligase 4, Cernunnos/XLF).