Changes in intra-host genetic diversity according to lesion severity in
longitudinal HPV16 samples.
Abstract
Human papillomavirus type 16 (HPV16) is the most common cause of
cervical cancer, but most infections are transient and with lesions not
progressing to cancer. There is a lack of specific biomarkers for
diagnosis and risk stratification. This study aimed to explore the
intra-host HPV16 genomic variation in longitudinal samples from
HPV16-infected women with different cervical lesion severity (normal,
low-grade, and high-grade). The TaME-seq deep sequencing protocol was
used to generate whole genome HPV16 sequences of 102 samples collected
over time from 40 individuals. Single nucleotide variants (SNVs) and
intra-host single nucleotide variants (iSNVs) were identified in the
viral genomes. A majority of individuals had a unique set of SNVs and
these SNVs were stable over time. Overall, the number of iSNVs and
APOBEC3-induced iSNVs were significantly lower in high-grade relative to
normal and low-grade samples, respectively. A significant increase in
the number of APOBEC3-induced iSNVs over time was observed for normal
samples when compared to high-grade. Our results provide new insight
into the dynamics of HPV16 within-hosts evolution. Low number of iSNVs
and APOBEC3-induced iSNVs, characteristics of high-grade lesions, could
potentially serve as biomarkers to guide triage of HPV-induced cervical
precancerous lesions.