{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,28]],"date-time":"2026-08-28T04:06:13Z","timestamp":1787889973538,"version":"build-2784847793"},"reference-count":20,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,9]],"date-time":"2023-08-09T00:00:00Z","timestamp":1691539200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hallym University Research Fund 2017","award":["HURF-2017-31"],"award-info":[{"award-number":["HURF-2017-31"]}]},{"name":"Hallym University Research Fund 2017","award":["2017R1C1B5017197"],"award-info":[{"award-number":["2017R1C1B5017197"]}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF) grant funded by the Korean government (Ministry of Science and ICT)","doi-asserted-by":"publisher","award":["HURF-2017-31"],"award-info":[{"award-number":["HURF-2017-31"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea (NRF) grant funded by the Korean government (Ministry of Science and ICT)","doi-asserted-by":"publisher","award":["2017R1C1B5017197"],"award-info":[{"award-number":["2017R1C1B5017197"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>The thymidine kinase (TK) and DNA polymerase (pol) genes of the herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) are two important genes involved in antiviral resistance. We investigated the genetic polymorphisms of the HSV-TK and pol genes in clinical isolates from Korean HSV-infected patients using next-generation sequencing (NGS) for the first time in Korea. A total of 81 HSV-1 and 47 HSV-2 isolates were examined. NGS was used to amplify and sequence the TK and pol genes. Among the 81 HSV-1 isolates, 12 and 17 natural polymorphisms and 9 and 23 polymorphisms of unknown significance in TK and pol were found, respectively. Two HSV-1 isolates (2.5%) exhibited the E257K amino acid substitution in TK, associated with antiviral resistance. Out of 47 HSV-2 isolates, 8 natural polymorphisms were identified in TK, and 9 in pol, with 13 polymorphisms of unknown significance in TK and 10 in pol. No known resistance-related mutations were observed in HSV-2. These findings contribute to our understanding of the genetic variants associated with antiviral resistance in HSV-1 and HSV-2 in Korea, with frequencies of known antiviral resistance-related mutations of 2.5% and 0% in HSV-1 and HSV-2, respectively.<\/jats:p>","DOI":"10.3390\/v15081709","type":"journal-article","created":{"date-parts":[[2023,8,9]],"date-time":"2023-08-09T10:08:59Z","timestamp":1691575739000},"page":"1709","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Variant Analysis of the Thymidine Kinase and DNA Polymerase Genes of Herpes Simplex Virus in Korea: Frequency of Acyclovir Resistance Mutations"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1040-1302","authenticated-orcid":false,"given":"Jungwon","family":"Hyun","sequence":"first","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong 18450, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Su Kyung","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong 18450, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji Hyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong 18450, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eun-Jung","family":"Cho","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong 18450, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Han-Sung","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang 14068, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6025-0341","authenticated-orcid":false,"given":"Jae-Seok","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Kangdong Sacred Heart Hospital, Seoul 05355, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5056-9033","authenticated-orcid":false,"given":"Wonkeun","family":"Song","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul 07441, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7026-6715","authenticated-orcid":false,"given":"Hyun Soo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Hallym University Dongtan Sacred Heart Hospital, Hallym University College of Medicine, Hwaseong 18450, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"654","DOI":"10.1097\/QCO.0000000000000288","article-title":"Antiviral resistance in herpes simplex virus and varicella-zoster virus infections: Diagnosis and management","volume":"29","author":"Piret","year":"2016","journal-title":"Curr. 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