@article{discovery10163462, volume = {18}, year = {2023}, title = {Utility of a buccal swab point-of-care test for the IFNL4 genotype in the era of direct acting antivirals for hepatitis C virus}, number = {1}, journal = {PLOS One}, note = {{\copyright} 2023 Sy et al. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/).}, publisher = {Public Library of Science (PLoS)}, url = {https://doi.org/10.1371/journal.pone.0280551}, author = {Sy, Aminata and McCabe, Leanne and Hudson, Emma and Ansari, Azim and Pedergnana, Vincent and Lin, Shang-Kuan and Fiorino, Marzia and ALA, Aftab and Stone, Ben and Smith, M and Nelson, Mark and Barclay, Stephen T and McPherson, Stuart and Ryder, Stephen and Collier, Jane and Barnes, Eleanor and Walker, Ann and Pett, Sarah L and Cooke, Graham}, abstract = {BACKGROUND: The CC genotype of the IFNL4 gene is known to be associated with increased Hepatitis C (HCV) cure rates with interferon-based therapy and may contribute to cure with direct acting antivirals. The Genedrive(R) IFNL4 is a CE marked Point of Care (PoC) molecular diagnostic test, designed for in vitro diagnostic use to provide rapid, real-time detection of IFNL4 genotype status for SNP rs12979860. METHODS: 120 Participants were consented to a substudy comparing IFNL4 genotyping results from a buccal swab analysed on the Genedrive(R) platform with results generated using the Affymetix UK Biobank array considered to be the gold standard. RESULTS: Buccal swabs were taken from 120 participants for PoC IFNL4 testing and a whole blood sample for genetic sequencing. Whole blood genotyping vs. buccal swab PoC testing identified 40 (33\%), 65 (54\%), and 15 (13\%) had CC, CT and TT IFNL4 genotype respectively. The Buccal swab PoC identified 38 (32\%) CC, 64 (53\%) CT and 18 (15\%) TT IFNL4 genotype respectively. The sensitivity and specificity of the buccal swab test to detect CC vs non-CC was 90\% (95\% CI 76-97\%) and 98\% (95\% CI 91-100\%) respectively. CONCLUSIONS: The buccal swab test was better at correctly identifying non-CC genotypes than CC genotypes. The high specificity of the Genedrive(R) assay prevents CT/TT genotypes being mistaken for CC, and could avoid patients being identified as potentially 'good responders' to interferon-based therapy.} }