Hákon Björn Högnason¹

Vigdís Fjóla Stefánsdóttir¹

Eirný Þöll Þórólfsdóttir¹

Jón Jóhannes Jónsson^1,2

Hans Tómas Björnsson^1,2,3

¹Department of Genetics and Molecular Medicine, Landspitali Hospital, ²Faculty of Medicine, University of Iceland, ³McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University.

Correspondence: Hákon Björn Högnason, hakonb@landspitali.is

Key words: genetic counselling, genetic testing, health care, genetic disease, genetic health care

 

Introduction: A genetic counselling unit at Landspitali hospital (LSH) was established in 2006. Meanwhile, genetic testing has become an integral part of general health care. In this article we detail the outcome of genetic testing at the Department of Genetic and Molecular Medicine (DGM) at Landspitali over a five year period (2012-2017). Factors that were analyzed for the time period were: Number of patients, reason for referral, reason for genetic testing without genetic counselling and yield (proportion of positive tests) of genetic testing.

Methods: Data was analysed from two medical record databases, Shire and Saga, used by the DGM in the time period.

Results: The number of individuals coming for genetic counselling increased every year over the time period. Reasons for referral were cancer-related in two-thirds of cases. Other reasons for referral included various other familial disorders. Most common were autosomal dominant disorders like myotonic dystrophy, hypertrophic cardiomyopathy and autosomal recessive disorders like spinal muscular atrophy (SMA) and GM1-gangliosidosis. Most common reasons for genetic testing outside of the LSH GC unit was because of managable diseases like hemochromatosis and F5/Prothrombin-related thrombophilia. Yield of genetic testing was assessed for a) known mutation testing / carrier testing, b) single gene testing, c) gene panel testing and d) whole genome and whole exome sequencing. Known mutation testing was positive in 33% of cases and single gene testing in 46% of cases. The yield of gene panel testing for cancer was found to be lower (20%) than gene panel testing for other disorders (40%). The yield of whole exome and whole genome sequencing was 46%.