Olivia King and Erica Dafoe, Cytogenetics Staff in the Laboratory Medicine Program at University Health Network presented at the Great Lakes Chromosome Conference (GLCC) on Friday, May 14.
Presenter: Olivia King
Title: All in, detecting a cryptic FGFR1 insertion using optical genome mapping
Hamilton Cytogenetics identified an insertion from chromosome 8 to chromosome 14. When UHN cancer cytogenetics lab did the follow-up karyotype, the insertion was no longer observed but a deletion in chromosome 8 where the previous rearrangement was. The Bionano Genomics Saphyr instrument was used to see if optical genome mapping would provide more information to help resolve the discrepancy. From the Bionano data, it was determined that the insertion was still present by ~50Kb, small enough that it not able to be seen by traditional karyotyping. Because of these results and in combination with the karyotyping and FISH findings, the patient was able to receive an FGFR1 inhibitor (pemigatinib) and responded immediately. This shows that optical genome mapping can provide additional cytogenetic findings that can sometimes not be seen by the current clinical standard!
Presenter: Erica Dafoe
Title: Cytogenetics says male, Molecular Diagnostics says female…Y?
Multiple testing revealed male karyotype by the Cytogenetics lab and female identity profile by Genome diagnostics lab. After further investigation to resolve the discrepancy, it was found out that there is a known deletion on the Y chromosome Amelogenin gene Yp11.1-11.2 region, which includes the drop out of the AMEL gene that affect persons with Indian ancestry. This 21 yr old male was presenting as a female identify profile as a result. Case closed!