Absence of cytomegalovirus in high-coverage DNA sequencing of human glioblastoma multiforme

Cytomegalovirus (CMV) has been proposed to be associated with glioblastoma multiforme, but there are conflicting results including lack of CMV mRNA in transcriptome sequencing data. Here, we utilized deep-coverage whole-genome sequencing data to detect latent CMV DNA in surgically resected tumors and to assess the relative proportions of viral and human DNA. We did not find traces of CMV in 52.6 billion DNA sequencing reads from 34 glioblastomas. By statistical analysis, we conclude that should the virus be present in these tumors, the average CMV level does not exceed one virus per 240,000 tumor cells (99% CI). What's new? While cytomegalovirus (CMV) has been functionally implicated in glioblastoma, its presence has been challenged by several reports, including lack of CMV mRNA in transcriptome studies. Here, the authors utilized deep-coverage whole-genome sequencing data to detect CMV DNA in surgically resected tumors. They found no traces of CMV in 52.6 billion DNA sequencing reads from 34 glioblastomas. Based on statistical analysis, they conclude that should the virus be present in these tumors, the average CMV level does not exceed one virus per 240,000 tumor cells (99% CI), effectively settling any remaining controversies regarding widespread presence of CMV DNA in glioblastoma.