Whole-Genome Sequence Analysis of Human Papillomavirus Type 18 from Infected Thai Women

Objective: The aim of this study was to attain molecular knowledge of human papillomavirus type 18 (HPV18) by sequencing the whole genome of HPV18 isolated from Thai women at various clinical stages of disease progression. Method: Our group analyzed 9 samples of whole-genome HPV18 in infected women ranging from normal to cervical cancer by PCR, a sequencing method and bioinformatics programs. Results: Phylogenetic analysis based on the whole genome showed that HPV18 samples were more closely related to the European and Asian-American type than the African type. The vaccine strain’s L1 nucleotide (US patent 5820870) showed a close relationship to the African type. However, our data cannot indicate the correlation between cytological data and nucleotide or amino acid variation. Conclusion: Our group cannot draw any inference between the clinical stage of disease progression and amino acid alterations as there were only 1 or 2 samples available for each clinical trial. However, we hope that these new data on the HPV genome, which are representative of the entire genome of HPV in Southeast Asia, can serve as basis data for future research on the pathogenesis of cervical cancer. Additionally, the second-generation HPV18 vaccines should be tested on both HPV18-L1 and HPV18-L2 for increasing potential protection.