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Onywera H, Maman D, Inzaule S, Auma E, Were K, Fredrick H, Owiti P, Opollo V, Etard JF, Mukui I, Kim AA, Zeh C. Surveillance of HIV-1 pol transmitted drug resistance in acutely and recently infected antiretroviral drug-naïve persons in rural western Kenya. PLoS One 2017; 12:e0171124. [PMID: 28178281 PMCID: PMC5298248 DOI: 10.1371/journal.pone.0171124] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 01/16/2017] [Indexed: 11/21/2022] Open
Abstract
HIV-1 transmitted drug resistance (TDR) is of increasing public health concern in sub-Saharan Africa with the rollout of antiretroviral (ARV) therapy. Such data are, however, limited in Kenya, where HIV-1 drug resistance testing is not routinely performed. From a population-based household survey conducted between September and November 2012 in rural western Kenya, we retrospectively assessed HIV-1 TDR baseline rates, its determinants, and genetic diversity among drug-naïve persons aged 15–59 years with acute HIV-1 infections (AHI) and recent HIV-1 infections (RHI) as determined by nucleic acid amplification test and both Limiting Antigen and BioRad avidity immunoassays, respectively. HIV-1 pol sequences were scored for drug resistance mutations using Stanford HIVdb and WHO 2009 mutation guidelines. HIV-1 subtyping was computed in MEGA6. Eighty seven (93.5%) of the eligible samples were successfully sequenced. Of these, 8 had at least one TDR mutation, resulting in a TDR prevalence of 9.2% (95% CI 4.7–17.1). No TDR was observed among persons with AHI (n = 7). TDR prevalence was 4.6% (95% CI 1.8–11.2) for nucleoside reverse transcriptase inhibitors (NRTIs), 6.9% (95% CI 3.2–14.2) for non- nucleoside reverse transcriptase inhibitors (NNRTIs), and 1.2% (95% CI 0.2–6.2) for protease inhibitors. Three (3.4% 95% CI 0.8–10.1) persons had dual-class NRTI/NNRTI resistance. Predominant TDR mutations in the reverse transcriptase included K103N/S (4.6%) and M184V (2.3%); only M46I/L (1.1%) occurred in the protease. All the eight persons were predicted to have different grades of resistance to the ARV regimens, ranging from potential low-level to high-level resistance. HIV-1 subtype distribution was heterogeneous: A (57.5%), C (6.9%), D (21.8%), G (2.3%), and circulating recombinant forms (11.5%). Only low CD4 count was associated with TDR (p = 0.0145). Our findings warrant the need for enhanced HIV-1 TDR monitoring in order to inform on population-based therapeutic guidelines and public health interventions.
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Affiliation(s)
- Harris Onywera
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
- * E-mail: (CZ); (HO)
| | - David Maman
- Epicentre, Médecins Sans Frontières (MSF), Paris, France
| | - Seth Inzaule
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Erick Auma
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Kennedy Were
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Harrison Fredrick
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Prestone Owiti
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Valarie Opollo
- Center for Global Health Research (CGHR), Kenya Medical Research Institute (KEMRI), Kisumu, Kenya
| | - Jean-François Etard
- TransVIHMI IRD UMI 233 –INSERM U 1175 –Université de Montpellier, Montpellier, France
| | - Irene Mukui
- National AIDS and STI Control Programme (NASCOP), Ministry of Health, Nairobi, Kenya
| | - Andrea A. Kim
- US Centers for Disease Control and Prevention (CDC), Nairobi, Kenya
| | - Clement Zeh
- US Centers for Disease Control and Prevention (CDC), Kisumu, Kenya
- * E-mail: (CZ); (HO)
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Wei X, Smith AJ, Forrest DW, Cardenas GA, Beck DW, LaLota M, Metsch LR, Sionean C, Owen SM, Johnson JA. Incident Infection and Resistance Mutation Analysis of Dried Blood Spots Collected in a Field Study of HIV Risk Groups, 2007-2010. PLoS One 2016; 11:e0159266. [PMID: 27415433 PMCID: PMC4944983 DOI: 10.1371/journal.pone.0159266] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 05/24/2016] [Indexed: 11/19/2022] Open
Abstract
Objective To assess the utility of cost-effective dried blood spot (DBS) field sampling for incidence and drug resistance surveillance of persons at high risk for HIV infection. Methods We evaluated DBS collected in 2007–2010 in non-clinical settings by finger-stick from HIV-positive heterosexuals at increased risk of HIV infection (n = 124), men who have sex with men (MSM, n = 110), and persons who inject drugs (PWID, n = 58). Relative proportions of recent-infection findings among risk groups were assessed at avidity index (AI) cutoffs of ≤25%, ≤30%, and ≤35%, corresponding to an infection mean duration of recency (MDR) of 220.6, 250.4, and 278.3 days, respectively. Drug resistance mutation prevalence was compared among the risk groups and avidity indices. Results HIV antibody avidity testing of all self-reported ARV-naïve persons (n = 186) resulted in 9.7%, 11.3% and 14.0% with findings within the 221, 250, and 278-day MDRs, respectively. The proportion of ARV-naïve MSM, heterosexuals, and PWID reporting only one risk category who had findings below the suggested 30% AI was 23.1%, 6.9% and 3.6% (p<0.001), respectively. MSM had the highest prevalence of drug resistance and the only cases of transmitted multi-class resistance. Among the ARV-experienced, MSM had disproportionately more recent-infection results than did heterosexuals and PWID. Conclusions The disproportionately higher recent-infection findings for MSM as compared to PWID and heterosexuals increased as the MDR window increased. Unreported ARV use might explain greater recent-infection findings and drug resistance in this MSM population. DBS demonstrated utility in expanded HIV testing; however, optimal field handling is key to accurate recent-infection estimates.
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Affiliation(s)
- Xierong Wei
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, 30329, United States of America
| | - Amanda J. Smith
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, 30329, United States of America
| | - David W. Forrest
- University of Miami, Miller School of Medicine, Miami, Florida, 33136, United States of America
| | - Gabriel A. Cardenas
- University of Miami, Miller School of Medicine, Miami, Florida, 33136, United States of America
| | - Dano W. Beck
- HIV/AIDS Section, Florida Department of Health, Tallahassee, Florida, 32399, United States of America
| | - Marlene LaLota
- HIV/AIDS Section, Florida Department of Health, Tallahassee, Florida, 32399, United States of America
| | - Lisa R. Metsch
- University of Miami, Miller School of Medicine, Miami, Florida, 33136, United States of America
| | - Catlainn Sionean
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, 30329, United States of America
| | - S. Michele Owen
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, 30329, United States of America
| | - Jeffrey A. Johnson
- Division of HIV/AIDS Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, 30329, United States of America
- * E-mail:
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Salimo AT, Ledwaba J, Coovadia A, Abrams EJ, Technau KG, Kuhn L, Morris L, Hunt GM. The use of dried blood spot specimens for HIV-1 drug resistance genotyping in young children initiating antiretroviral therapy. J Virol Methods 2015; 223:30-2. [PMID: 26192603 DOI: 10.1016/j.jviromet.2015.07.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 07/09/2015] [Accepted: 07/10/2015] [Indexed: 11/16/2022]
Abstract
Paired plasma and dried blood spots (DBS) from 232 South African HIV-infected children initiating antiretroviral therapy (ART) were genotyped for drug resistance mutations, most of who had prior exposure to ART for prevention-of-mother-to-child-transmission. Non-nucleoside reverse transcriptase inhibitor mutations were most commonly detected in both specimen types, particularly Y181C/I and K103N/S. Resistance interpretation concordance was achieved in 97% of pairs with seven children having mutations detected in DBS only. These results validate the preferential use of DBS specimens for HIVDR genotyping in this patient group.
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Affiliation(s)
- Anna T Salimo
- Centre for HIV and STIs, National Institute for Communicable Diseases, National Health Laboratory Services, Johannesburg, South Africa.
| | - Johanna Ledwaba
- Centre for HIV and STIs, National Institute for Communicable Diseases, National Health Laboratory Services, Johannesburg, South Africa.
| | - Ashraf Coovadia
- Empilweni Services and Research Unit, Rahima Moosa Mother and Child Hospital, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Elaine J Abrams
- ICAP, Mailman School of Public Health, and College of Physicians & Surgeons, Columbia University, New York, USA.
| | - Karl-Günter Technau
- Empilweni Services and Research Unit, Rahima Moosa Mother and Child Hospital, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Louise Kuhn
- Gertrude H. Sergievsky Center, College of Physicians and Surgeons, and Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, USA.
| | - Lynn Morris
- Centre for HIV and STIs, National Institute for Communicable Diseases, National Health Laboratory Services, Johannesburg, South Africa; Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
| | - Gillian M Hunt
- Centre for HIV and STIs, National Institute for Communicable Diseases, National Health Laboratory Services, Johannesburg, South Africa; Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
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Antiretroviral treatment outcome in HIV-1-infected patients routinely followed up in capital cities and remote areas of Senegal, Mali and Guinea-Conakry. J Int AIDS Soc 2014; 17:19315. [PMID: 25527333 PMCID: PMC4272405 DOI: 10.7448/ias.17.1.19315] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Revised: 11/02/2014] [Accepted: 11/03/2014] [Indexed: 11/23/2022] Open
Abstract
Introduction Access to antiretroviral treatment (ART) becomes more and more effective in resource-limited settings (RLS). However, this global effort would be even more profitable if the access to laboratory services especially in decentralized settings was strengthened. We report the virological outcome and HIV-1 drug resistance in three West African countries using dried blood spots (DBS) samples.
Methods We included HIV-1-infected adults on ART ≥6 months and followed up in capital cities and decentralized sites in Senegal, Mali and Guinea-Conakry. Patients were consecutively enrolled and DBS were collected in field conditions and kept at ambient temperature before transfer to the reference laboratory. Viral load (VL) was quantified using the NucliSENS EasyQ HIV-1 v1.2. Genotyping of HIV-1 pol gene was performed using in-house protocol. Results Of the 407 participants, 119, 152 and 136 were from Senegal, Mali and Guinea-Conakry, respectively. The median treatment duration was 36 months [IQR: 6–136]. Virological failure (VF) (VL≥3log10 copies/mL) was observed in 26% (95% confidence interval (CI), 18–35; n=31), 11% (95% CI, 6–17; n=16) and 24% (95% CI, 17–32; n=33) of patients in Senegal, Mali and Guinea-Conakry, respectively (p=0.001). Of samples presenting VL≥3log10 copies/mL (n=80), 70 were successfully genotyped. At least one drug resistance mutation (DRM) was detected in the following proportions: 70% (95% CI, 50–86; n=19), 93% (95% CI, 68–100; n=14) and 68% (95% CI, 48–84; n=19) in Senegal, Mali and Guinea-Conakry, respectively (p=0.22). Twenty-six per cent (26%; 95% CI, 16–38; n=18) of patients in VF harboured wild-type viruses, which is likely indicative of weak adherence. Phylogenetic analysis showed the predominance of CRF02_AG subtype (73%; 95% CI, 61–83; n=51). Conclusions We describe the ART outcome in capital and rural settings of Senegal, Mali and Guinea-Conakry. Our results in all of the three countries highlight the need to reinforce the ART adherence in order to minimize the occurrence of drug resistance. In addition, these findings provide additional evidence that the use of DBS as a sampling support could assist virological monitoring of patients on ART in remote areas.
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Kijak GH, Sanders-Buell E, Harbolick EA, Pham P, Chenine AL, Eller LA, Rono K, Robb ML, Michael NL, Kim JH, Tovanabutra S. Targeted deep sequencing of HIV-1 using the IonTorrentPGM platform. J Virol Methods 2014; 205:7-16. [PMID: 24797459 DOI: 10.1016/j.jviromet.2014.04.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2014] [Revised: 04/11/2014] [Accepted: 04/25/2014] [Indexed: 10/25/2022]
Abstract
The characterization of mixed HIV-1 populations is a key question in clinical and basic research settings. This can be achieved through targeted deep sequencing (TDS), where next-generation sequencing is used to examine in depth a sub-genomic region of interest. This study explores the suitability of IonTorrent PGM(LifeTechnologies) for the TDS-based analysis of HIV-1 evolution. Using laboratory reagents and primary specimens sampled at pre-peak viremia the error rates from misincorporation and in vitro recombination were <0.5%. The sequencing error rate was 2- to 3-fold higher in/around homopolymeric tracts, and could be discerned from true polymorphism using bidirectional sequencing. The limit of detection of complex variants was further lowered by using haplotyping. The application of this system was illustrated on primary samples from an individual infected with HIV-1 followed from pre-peak viremia through six months post-acquisition. TDS provided an augmented view of the extent of genetic diversity, the covariation among polymorphisms, the evolutionary pathways, and the boundaries of the mutational space explored by the viral swarm. Based on its performance, the system can be applied for the characterization of minor viral variants in support of studies of viral evolution, which can inform the rational design of the next generation of vaccines and therapeutics.
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Affiliation(s)
- Gustavo H Kijak
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA.
| | - Eric Sanders-Buell
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Elizabeth A Harbolick
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Phuc Pham
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Agnes L Chenine
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Leigh Anne Eller
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Kathleen Rono
- Kenya Medical Research Institute/Walter Reed Project, Kericho, Kenya
| | - Merlin L Robb
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
| | - Nelson L Michael
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Jerome H Kim
- U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, MD, USA
| | - Sodsai Tovanabutra
- U.S. Military HIV Research Program, Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA
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Ji H, Li Y, Liang B, Pilon R, MacPherson P, Bergeron M, Kim J, Graham M, Van Domselaar G, Sandstrom P, Brooks J. Pyrosequencing dried blood spots reveals differences in HIV drug resistance between treatment naïve and experienced patients. PLoS One 2013; 8:e56170. [PMID: 23409150 PMCID: PMC3567018 DOI: 10.1371/journal.pone.0056170] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Accepted: 01/07/2013] [Indexed: 11/18/2022] Open
Abstract
Dried blood spots (DBS) are an alternative specimen collection format for HIV-1 genotyping. DBS produce HIV genotyping results that are robust and equivalent to plasma when using conventional sequencing methods. However, using tagged, pooled pyrosequencing, we demonstrate that concordance between plasma and DBS is not absolute and varies according to viral load (VL), duration of HIV infection and antiretroviral therapy (ART) status. The plasma/DBS concordance is the highest when VL is ≥5,000 copies/ml and/or the patient has no ART exposure and/or when the duration of HIV infection is ≤2 years. Stepwise regression analysis revealed that VL is most important independent predictor for concordance of DBS with plasma genotypes. This is the first study to use next generation sequencing to identify discordance between DBS and plasma genotypes. Consideration should be given to VL, duration of infection, and ART exposure when interpreting DBS genotypes produced using next generation sequencing. These findings are of particular significance when DBS are to be used for clinical monitoring purposes.
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Affiliation(s)
- Hezhao Ji
- National HIV & Retrovirology Laboratories, National Microbiology Laboratory, Public Health Agency of Canada, Ottawa, Canada
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Design and development of an in-house multiplex RT-PCR assay for simultaneous detection of HIV-1 and HCV in plasma samples. IRANIAN JOURNAL OF MICROBIOLOGY 2012; 52:456-63. [PMID: 22783455 DOI: 10.1007/s12088-012-0271-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2011] [Accepted: 04/26/2012] [Indexed: 01/12/2023]
Abstract
BACKGROUND AND OBJECTIVES HIV-1 and HCV infections are life threatening problems in patients who receive blood products. Serological methods have proven useful in detecting these infections, but there are setbacks that make it challenging to detect these infectious agents. By the advent of Nucleic Acid Testing (NAT) methods, especially in multiplex format, more precise detection is possible. MATERIALS AND METHODS We have developed a multiplex RT-PCR assay for simultaneous detection of HIV-1 and HCV. Primers were designed for highly conserved region of genome of each virus. Using these primers and standard plasmids, we determined the limit of detection, clinical and analytical specificity and sensitivity of the assay. Monoplex and multiplex RT-PCR were performed. RESULTS Analytical sensitivity was considered to be 100 and 200 copies/ml for HIV-1 and HCV, respectively. High concentration of one virus had no significant effect on the detection of the other one with low concentration. By analysis of 40 samples, clinical sensitivity of the assay was determined to be 97.5%. Using different viral and human genome samples, the specificity of the assay was evaluated to be 100%. CONCLUSIONS The aim of this study was to develop a reliable, rapid and cost effective method to detect HIV-1 and HCV simultaneously. Results showed that this simple and rapid method is perfectly capable of detecting two viruses in clinical samples.
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Factors limiting the transmission of HIV mutations conferring drug resistance: fitness costs and genetic bottlenecks. Sci Rep 2012; 2:320. [PMID: 22432052 PMCID: PMC3307053 DOI: 10.1038/srep00320] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Accepted: 02/20/2012] [Indexed: 11/08/2022] Open
Abstract
Transmission of HIV strains with drug-resistance mutations (DRMs) causes public health problems in resource-rich countries. We use a stochastic model, with data from viral competition experiments, to analyze the effect of fitness costs (FCs) and genetic bottlenecks on limiting transmission of 10 clinically significant DRMs. Transmission of DRMs with low FCs (∼0.2%) is similar to wild-type; transmission chains last ∼8 generations causing clusters of ∼60 infected individuals. Genetic bottlenecks substantially limit transmission of DRMs with moderately high FCs (∼0.6%); chains last ∼1–3 generations with transmission clusters of 2–7. Transmission of DRMs with extremely high FCs (>6%) only occurs from ∼5% of index cases. DRMs can revert to wild-type and remain as minority strains, within treatment-naïve individuals, undetectable by current resistance assays. We calculate, based on assay sensitivity, the length of time each DRM is detectable within individuals. Taken together, our results imply a hidden epidemic of transmitted resistance may exist.
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Halfon P, Ouzan D, Khiri H, Pénaranda G, Castellani P, Oulès V, Kahloun A, Amrani N, Fanteria L, Martineau A, Naldi L, Bourlière M. Detection of IL28B SNP DNA from buccal epithelial cells, small amounts of serum, and dried blood spots. PLoS One 2012; 7:e33000. [PMID: 22412970 PMCID: PMC3296767 DOI: 10.1371/journal.pone.0033000] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Accepted: 02/02/2012] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND & AIMS Point mutations in the coding region of the interleukin 28 gene (rs12979860) have recently been identified for predicting the outcome of treatment of hepatitis C virus infection. This polymorphism detection was based on whole blood DNA extraction. Alternatively, DNA for genetic diagnosis has been derived from buccal epithelial cells (BEC), dried blood spots (DBS), and genomic DNA from serum. The aim of the study was to investigate the reliability and accuracy of alternative routes of testing for single nucleotide polymorphism allele rs12979860CC. METHODS Blood, plasma, and sera samples from 200 patients were extracted (400 µL). Buccal smears were tested using an FTA card. To simulate postal delay, we tested the influence of storage at ambient temperature on the different sources of DNA at five time points (baseline, 48 h, 6 days, 9 days, and 12 days). RESULTS There was 100% concordance between blood, plasma, sera, and BEC, validating the use of DNA extracted from BEC collected on cytology brushes for genetic testing. Genetic variations in HPTR1 gene were detected using smear technique in blood smear (3620 copies) as well as in buccal smears (5870 copies). These results are similar to those for whole blood diluted at 1/10. A minimum of 0.04 µL, 4 µL, and 40 µL was necessary to obtain exploitable results respectively for whole blood, sera, and plasma. No significant variation between each time point was observed for the different sources of DNA. IL28B SNPs analysis at these different time points showed the same results using the four sources of DNA. CONCLUSION We demonstrated that genomic DNA extraction from buccal cells, small amounts of serum, and dried blood spots is an alternative to DNA extracted from peripheral blood cells and is helpful in retrospective and prospective studies for multiple genetic markers, specifically in hard-to-reach individuals.
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Affiliation(s)
- Philippe Halfon
- Laboratoire Alphabio, Hôpital Ambroise Paré, Marseille, France.
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