Rebecca Reid1, Jodie Fitness 1, Emmie Pushkareff 1, Redmond Orth 1, Aynsley Bryce 1, Nick Hovey 1, Dr Melody Caramins 2, Dr Nicole Chia1
1 Queensland Medical Laboraory, Metroplex on Gateway, 11 Riverview Pl, Murarrie, QLD, 4172
2 Genomic Diagnostics, 60 Waterloo Road, Macquarie Park, NSW, 2113
Conventional karyotyping and targeted fluorescence in-situ hybridisation (FISH) analysis have long been the gold standard of cytogenetic investigation for haematological malignancies. The detection of non-random balanced rearrangements and duplication and deletion that is associated with gene deregulation, formation of chimeric protein or unmasking of tumour suppressor gene mutations, is the primary objective of these investigations.
The higher level of resolution afforded by molecular karyotyping by microarray has characterised some of the well described duplications and deletions with respect to genomic location and gene involvement. Copy number changes, and where SNP microarray platforms are applied, non-random events of acquired uniparental disomy (aUPD) that are beyond the scope of conventional analysis have been detected.
Here we review the conventional and molecular karyotypes of haematological malignancies (CLL and myeloid malignancies) referred to a diagnostic service. The objective of this study is to investigate events of aUPD, identify the putative candidate genes within these regions and evaluate the impact to the prognostic significance when compared to the conventional cytogenetic results. Preliminary findings reveal an incidence of 12.6% of non-random events of aUPD involving primarily chromosomes 1, 9, 13, 17 and 20, some of which, such as aUPD 17p, alter the prognostic significance from the low risk to high risk clinical category. Comparison of genomic locations of aUPD demonstrated a correlation with the type of haematological malignancy.
This study illustrates the benefits of SNP based microarray investigation as an adjunct to conventional methods for the comprehensive investigation of haematological malignancies and progression towards precision medicine.
Since graduating from Massey University in New Zealand at the end of 2015, Rebecca has been employed in the Genetics Department at QML Pathology, primarily working in haem-oncology.