As a contribution to the public health authorities in planning prophylactic and therapeutic vaccine strategies, we describe the prevalence of human papillomavirus (HPV)
More than 100 HPV types have been described, 13 of which are classified as high-risk due to their association with the development of cervical cancer. The intratype genomic diversity of HPV-16 and -18 has been studied extensively, while little data have been generated for other less common high-risk types. The present study explores the nucleotide variability and phylogeny of the high-risk HPV-31, -33, -35, -52, and -58, in samples from Central Brazil. For this purpose, the LCR and the E6 and L1 genes were sequenced. Several variants of these HPV types were detected, some of which have been detected in other parts of the world. Furthermore, new variants of all types examined were characterized in a total of 13 new variants. Based on the E6 and L1 sequences, variants were described comprising conservative and non-conservative amino acid changes. For phylogenetic tree construction, samples characterized in this study were compared to others described and submitted to GenBank previously. The phylogenetic analysis of HPV-31, -33, -35, and -58 isolates did not reveal ethnic or geographical clustering as observed previously for HPV-16 and -18. HPV-35 analysis showed a dichotomic branching characteristic of viral subtypes. Interestingly, four clusters relative to the analysis of HPV-52 isolates were identified, two of which could be classified as Asian and European branches. The genomic characterization of HPV variants is crucial for understanding the intrinsic geographical relatedness and biological differences of these viruses and contributes further to studies on their infectivity and pathogenicity.
HPV-18 is the second most prevalent human papillomavirus genotype found in cervical cancer. Nucleotide variations in HPV-18 sequence can interfere with the viral oncogenic potential. However, the knowledge about HPV-18 variants in Brazil is still limited. The present study aims to determine the LCR, E6, and L1 genetic variability of HPV-18 variants found in women co-infected with HIV-1 in Central Brazil. Four HPV-18 samples were identified and had the LCR, E6, and L1 genomic regions sequenced. It was possible to characterize three European variants and one African variant of HPV-18. All of them are new variants, showing nucleotide substitutions not previously reported. Nucleotide variations in binding sites for transcriptional factors were observed. Phylogenetic analysis was also performed, evidencing the three clusters related to the Asian-American, African, and European variants. The characterization of HPV genetic variability is of pivotal importance to the understanding of the viral pathogenicity.
The present study on genetic diversity of human papillomaviruses in women infected by HIV in Brazil describes the frequency, the genotypes, and five new variants of HPV. One hundred fifty cervical smears of HIV-positive women were subjected to cytological examination, and the DNA samples obtained were assayed by MY09/MY11 amplification, followed by RFLP typing. The overall HPV-DNA-positive rate was 42.7%. One hundred twenty-two samples (81.3%) had benign cellular alterations or normal cytological results, and HPV DNA frequency among them was 30.3%. Otherwise, 96.4% of samples with altered cytology were positive for HPV DNA. A high diversity of genotypes was observed. HPVs-16 and 81 were the most prevalent (14.1%) and were followed by HPVs 52, 35, 62, 33, 53, 56, 66, 70, 18, 58, 6b, 11, 31, 39, 40, 61, 71, 32, 54, 59, 67, 68, 85, and 102. Five new variants of the high-risk HPVs 18, 33, 53, 59, and 66 were detected. Possible associations between the detection of HPV genotypes and the cytological classification, HIV viral load, CD4 count, and antiretroviral treatment were also examined. We observed that a high proportion of HIV-infected women are infected with HPV and may carry oncogenic genotypes, even when cytological evaluation shows normal results.
Leafroll is an economically important disease affecting grapevines (Vitis spp.). Nine serologically distinct viruses, Grapevine leafroll-associated virus-1 through 9, are associated with this disease. The present study describes the coat protein gene sequence of four GLRaV-3 isolates occurring in the São Francisco River basin, Northeastern Brazil. The viral RNA was extracted from GLRaV-3 ELISA-positive plants and the complete coat protein gene was amplified by RT-PCR. Sequences were generated automatically and compared to the complete coat protein sequence from North American (NY1) and Chinese (Dawanhong Nº2 and SL10) GLRaV-3 isolates. The four studied isolates, named Pet-1 through 4, showed deduced amino acid identities of 98-100% (Pet-1 through 3) and 95% (Pet-4) with North American and Chinese isolates. A total of seventeen amino acid substitutions was detected among the four characterized isolates in comparison to the NY1, Dawanhong No.2 and SL10 sequences. The results indicated the existence of natural variation among GLRaV-3 isolates from grapevines, also demonstrating a lack of correlation between sequence data and geographic origin. This variability should be considered when selecting regions of the viral genome targeted for reliable and consistent virus molecular detection.Additional keywords: Closteroviridae, Ampelovirus, GLRaV-3. RESUMOVariabilidade do gene da proteína capsidial do Grapevine leafroll-associated virus 3 no Brasil O enrolamento da folha é uma doença economicamente importante que afeta videiras (Vitis spp.). Nove vírus sorologicamente distintos, Grapevine leafroll-associated virus-1 a -9, estão associados à doença. Este estudo descreve a seqüência do gene da proteína capsidial de quatro isolados do GLRaV-3 encontrados no Vale do Rio São Francisco, Nordeste do Brasil. O RNA viral foi extraído de plantas positivas em ELISA para o GLRaV-3 e o gene da proteína capsidial completo foi amplificado por RT-PCR. As seqüências foram geradas automaticamente e comparadas a seqüências completas do gene da proteína capsidial de isolados Norte-Americano (NY1) e Chineses (Dawanhong N°2 e SL10) de GLRaV-3. Os quatro isolados estudados, denominados Pet-1 a 4, exibiram identidades de aminoácidos deduzidos de 98-100% (Pet-1 a 3) e 95% (Pet-4) com os isolados Norte-Americano e Chineses. Um total de dezessete substituições de aminoácidos foi detectado entre os quatro isolados caracterizados em comparação com as seqüências do NY1, Dawanhong No.2 e SL10. Os resultados indicaram a existência de variação natural entre os isolados de GLRaV-3 de videiras, demonstrando também a falta de correlação entre dados de sequência e origem geográfica. Esta variabilidade deve ser considerada quando se selecionam regiões do genoma viral para uma detecção molecular confiável e consistente.Palavras-chave adicionais: Closteroviridae, Ampelovirus, GLRaV-3.
We report the prevalence of human papillomavirus type
HPV-16 is the most prevalent human papillomavirus genotype found in cervical intraepithelial neoplasias. The regulatory region of the HPV genome, LCR, has several binding sites for cellular and viral transcription factors, and nucleotide substitutions in this genomic region can interfere with the viral oncogenic expression. The present study aims to determine the LCR variability of European and non-European HPV-16 variants found in Brazil. Through automated sequencing, it was possible to characterize the LCR of ten non-European (eight Asian-American, one African 1, one African 2) and twelve European isolates. Among the 22 isolates analyzed, nine may be new variants of HPV-16, with different combinations of previously reported nucleotide substitutions, and three showed new substitutions not previously reported. Two new nucleotide substitutions, the insertion of T at position 7621 and the substitution of A to G at position 7836, were found in a single isolate, Bsb-14, a putative new African 1 variant. The characterization of the LCR of human papillomaviruses can be of pivotal importance to the understanding of the viral replication and pathogenicity.
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