DSP in Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC)

The role of rare variants in DSP as causative mutations in Arrhythmogenic Right Ventricular Cardiomyopathy is described below. By comparing the frequency of DSP variants in large ARVC clinical cohorts to the background population rate in the ExAC database, the proportion of ARVC patients with pathogenic mutations in DSP can be estimated, as well as the likelihood that a rare (population allele frequency <0.0001) DSP variant identified in a ARVC patient is disease-causing. Summary data for different variant classes (all protein-altering variants, loss of function truncating variants and non-truncating variants) is highlighted - see the table below for full details of this analysis.


Excess of DSP variants in ARVC: 9.07% (p<0.0001)

Based on an analysis of all rare protein-altering variants (MAF<0.0001 in ExAC) in DSP found in 352 ARVC samples sequenced by OMGL and in reference samples of the ExAC population database.


Metrics by Variant Class:
All VarsTruncatingNon-Truncating
Excess in ARVC 9.07%
p<0.0001
5.90%
p<0.0001
3.17%
p=0.0018
Etiological fraction 0.77
0.67 - 0.83
0.99
0.98 - 0.99
0.52
0.23 - 0.69
Odds Ratio 4.28
3.03 - 5.93
89.98
50.00 - 157.34
2.10
1.30 - 3.24

The Etiological Fraction (EF) is the proportion of affected carriers where the variant caused ARVC. The Odds Ratio (OR) describes the odds of having a rare variant in the patient cohort to the odds in the ExAC cohort. Fisher's exact test p-values are displayed for case excess, 95% confidence intervals for EFs and ORs.



SourceSamples
Tested
Variant
Type
Variants
detected
Frequency
in ARVC
Frequency
in ExAC
Case Excess
in ARVC
OMGL1352All43 0.122160.031480.09068
Truncating21 0.059660.000700.05896
Non-Truncating22 0.062500.030780.03172

References

1. Roddy Walsh, Kate L. Thomson, James S. Ware, Birgit H. Funke, Jessica Woodley, Karen J. McGuire, Francesco Mazzarotto, Edward Blair, Anneke Seller, Jenny C. Taylor, Eric V. Minikel, Exome Aggregation Consortium, Daniel G. MacArthur, Martin Farrall, Stuart A. Cook and Hugh Watkins. Reassessment of Mendelian gene pathogenicity using 7,855 cardiomyopathy cases and 60,706 reference samples. Genet Med. 2016 doi:10.1038/gim.2016.90.