Todesco E, et al. - Researchers sequenced HIV pol gene fragments by ultradeep sequencing (UDS) and performed Sanger sequencing on samples of 70 HIV-1-infected, treatment-naive recently diagnosed MSM to investigate HIV-1 epidemiological linkage and to assess characteristics of transmission dynamics and transmitted drug resistance (TDR) detection. As per findings, same transmission chains were identified with Sanger sequencing and UDS. However, additional information on founder viruses, direction of transmission and levels of TDR was gained using UDS. Nonetheless, as across gene fragments, the topology of clusters was not always consistent, a cautious interpretation of the data is recommended. Moreover, no dismissal of the possibility of unobserved intermediary links could be made. The findings thus suggest that as a forensic technique for HIV transmission investigations, phylogenetic analysis use seems risky.