Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil

<b>Background/Objectives:</b> Human cytomegalovirus (HCMV) DNAemia remains a significant concern for transplant recipients, largely due to mutations in the viral genome that may lead to antiviral-resistant strains. Mutations in the <i>UL97</i> gene are frequently associated w...

Full description

Saved in:
Bibliographic Details
Main Authors: Anna Caroline Avila da Rocha, Grazielle Motta Rodrigues, Alessandra Helena da Silva Hellwig, Dariane Castro Pereira, Fabiana Caroline Zempulski Volpato, Afonso Luís Barth, Fernanda de-Paris
Format: Article
Language:English
Published: MDPI AG 2025-01-01
Series:Diagnostics
Subjects:
Online Access:https://www.mdpi.com/2075-4418/15/2/214
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832588701854597120
author Anna Caroline Avila da Rocha
Grazielle Motta Rodrigues
Alessandra Helena da Silva Hellwig
Dariane Castro Pereira
Fabiana Caroline Zempulski Volpato
Afonso Luís Barth
Fernanda de-Paris
author_facet Anna Caroline Avila da Rocha
Grazielle Motta Rodrigues
Alessandra Helena da Silva Hellwig
Dariane Castro Pereira
Fabiana Caroline Zempulski Volpato
Afonso Luís Barth
Fernanda de-Paris
author_sort Anna Caroline Avila da Rocha
collection DOAJ
description <b>Background/Objectives:</b> Human cytomegalovirus (HCMV) DNAemia remains a significant concern for transplant recipients, largely due to mutations in the viral genome that may lead to antiviral-resistant strains. Mutations in the <i>UL97</i> gene are frequently associated with resistance to ganciclovir (GCV), highlighting the importance of early mutation detection to effectively manage viremia. This study aimed to optimize a Sanger sequencing protocol for analyzing GCV resistance-linked mutations in the HCMV <i>UL97</i> gene from plasma samples of transplant patients treated at Hospital de Clínicas de Porto Alegre, Rio Grande do Sul, Brazil. <b>Methods:</b> A nested-PCR approach combined with a touchdown PCR method was employed to enhance the sensitivity and specificity of the sequencing analysis. <b>Results:</b> The study sample included various transplants, encompassing solid organ and bone marrow recipients. Among 16 sequenced samples, 8 exhibited nucleotide substitutions resulting in amino acid changes. Notably, the A594V and C603W mutations, associated with GCV resistance, were identified in four samples. Additionally, three mutations with unknown phenotypic impact (P509L, A628T, and H662Y) and two viral polymorphisms (N510S and D605E) were detected. Furthermore, double peaks in the Sanger electropherograms, indicative of mixed viral populations of HCMV were observed in seven samples. <b>Conclusions:</b> The optimized Sanger sequencing protocol provides a cost-effective solution for detecting GCV resistance mutations in HCMV <i>UL97</i> among transplant recipients. This approach could improve the understanding of HCMV strain dynamics and serve as a valuable tool for long-term patient monitoring, particularly within resource-constrained settings such as the public health systems of middle-income countries.
format Article
id doaj-art-6a7abb76b6d947d0af589547e2e560e5
institution Kabale University
issn 2075-4418
language English
publishDate 2025-01-01
publisher MDPI AG
record_format Article
series Diagnostics
spelling doaj-art-6a7abb76b6d947d0af589547e2e560e52025-01-24T13:29:08ZengMDPI AGDiagnostics2075-44182025-01-0115221410.3390/diagnostics15020214Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern BrazilAnna Caroline Avila da Rocha0Grazielle Motta Rodrigues1Alessandra Helena da Silva Hellwig2Dariane Castro Pereira3Fabiana Caroline Zempulski Volpato4Afonso Luís Barth5Fernanda de-Paris6Faculdade de Biomedicina, Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre 90050-170, Rio Grande do Sul, BrazilPrograma de Pós-Graduação em Ciências Médicas, Universidade Federal do Rio Grande do Sul, Porto Alegre 90160-093, Rio Grande do Sul, BrazilPrograma de Pós-Graduação em Ciências Médicas, Universidade Federal do Rio Grande do Sul, Porto Alegre 90160-093, Rio Grande do Sul, BrazilLABRESIS–Laboratório de Pesquisa em Resistência Bacteriana, Hospital de Clínicas de Porto Alegre, Porto Alegre 90035-903, Rio Grande do Sul, BrazilDepartamento de Biociências, Universidade Federal do Paraná, Setor Palotina, Palotina 85953-128, Paraná, BrazilLABRESIS–Laboratório de Pesquisa em Resistência Bacteriana, Hospital de Clínicas de Porto Alegre, Porto Alegre 90035-903, Rio Grande do Sul, BrazilLABRESIS–Laboratório de Pesquisa em Resistência Bacteriana, Hospital de Clínicas de Porto Alegre, Porto Alegre 90035-903, Rio Grande do Sul, Brazil<b>Background/Objectives:</b> Human cytomegalovirus (HCMV) DNAemia remains a significant concern for transplant recipients, largely due to mutations in the viral genome that may lead to antiviral-resistant strains. Mutations in the <i>UL97</i> gene are frequently associated with resistance to ganciclovir (GCV), highlighting the importance of early mutation detection to effectively manage viremia. This study aimed to optimize a Sanger sequencing protocol for analyzing GCV resistance-linked mutations in the HCMV <i>UL97</i> gene from plasma samples of transplant patients treated at Hospital de Clínicas de Porto Alegre, Rio Grande do Sul, Brazil. <b>Methods:</b> A nested-PCR approach combined with a touchdown PCR method was employed to enhance the sensitivity and specificity of the sequencing analysis. <b>Results:</b> The study sample included various transplants, encompassing solid organ and bone marrow recipients. Among 16 sequenced samples, 8 exhibited nucleotide substitutions resulting in amino acid changes. Notably, the A594V and C603W mutations, associated with GCV resistance, were identified in four samples. Additionally, three mutations with unknown phenotypic impact (P509L, A628T, and H662Y) and two viral polymorphisms (N510S and D605E) were detected. Furthermore, double peaks in the Sanger electropherograms, indicative of mixed viral populations of HCMV were observed in seven samples. <b>Conclusions:</b> The optimized Sanger sequencing protocol provides a cost-effective solution for detecting GCV resistance mutations in HCMV <i>UL97</i> among transplant recipients. This approach could improve the understanding of HCMV strain dynamics and serve as a valuable tool for long-term patient monitoring, particularly within resource-constrained settings such as the public health systems of middle-income countries.https://www.mdpi.com/2075-4418/15/2/214cytomegalovirusmutationganciclovir resistancetransplant recipients
spellingShingle Anna Caroline Avila da Rocha
Grazielle Motta Rodrigues
Alessandra Helena da Silva Hellwig
Dariane Castro Pereira
Fabiana Caroline Zempulski Volpato
Afonso Luís Barth
Fernanda de-Paris
Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil
Diagnostics
cytomegalovirus
mutation
ganciclovir resistance
transplant recipients
title Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil
title_full Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil
title_fullStr Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil
title_full_unstemmed Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil
title_short Ganciclovir Resistance-Linked Mutations in the HCMV <i>UL97</i> Gene: Sanger Sequencing Analysis in Samples from Transplant Recipients at a Tertiary Hospital in Southern Brazil
title_sort ganciclovir resistance linked mutations in the hcmv i ul97 i gene sanger sequencing analysis in samples from transplant recipients at a tertiary hospital in southern brazil
topic cytomegalovirus
mutation
ganciclovir resistance
transplant recipients
url https://www.mdpi.com/2075-4418/15/2/214
work_keys_str_mv AT annacarolineaviladarocha ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil
AT graziellemottarodrigues ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil
AT alessandrahelenadasilvahellwig ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil
AT darianecastropereira ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil
AT fabianacarolinezempulskivolpato ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil
AT afonsoluisbarth ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil
AT fernandadeparis ganciclovirresistancelinkedmutationsinthehcmviul97igenesangersequencinganalysisinsamplesfromtransplantrecipientsatatertiaryhospitalinsouthernbrazil