Causes and consequences of structural genomic alterations in the human genome

The revolutionary development and application of microarray-based comparative genomic hybridisation (aCGH) technology within the past decade or so represents a profound and continuing fundamental contribution to the molecular dissection and characterisation of complex human disorders: disorders ranging from developmental pathologies including intellectual disability, schizophrenia and autism spectrum disorders to more common conditions such as cancer. A unifying underlying feature here is that these disorders are associated with complex structural rearrangements in chromosomes. aCGH technology application has also enabled the refinement of ‘old’ and identification of ‘new’ mechanisms to explain the origin of these complex chromosomal alterations. Interestingly, these structural variations can also incorporate genes whose products play fundamental roles in aspects of deoxyribonucleic acid repair, replication and recombination, thereby having an impact on genome-wide stability and integrity. In this article, the mechanisms underlying complex structural chromosomal rearrangements are reviewed and their implications with respect to genome-wide stability are discussed.