The present invention relates to HGyV, a human gyrovirus related to the chicken anemia virus (CAV). The present invention also relates to a new proteins encoded by HGyV, which proteins display some homology to CAV proteins. Among these new proteins, H-apoptin is of particular interest as it is herein found for the first time in a human virus and can be used for treating cancer. Also provided are methods for detecting the HGyV virus in a subject.
