Polymerase chain reaction (PCR)-based genital human papillomavirus (HPV) detection methods that use consensus primers have enabled the broad-spectrum detection of most characterized HPV types. In addition, these techniques have allowed the identification of potentially novel viral sequences in clinical specimens. These methods were used to determine the partial Ll nucleotide sequence (the region generated by Ll consensus primers MY09 and MY11) of four novel viruses. The prevalence of these viruses in cytologically normal and dysplastic cervical specimens and in invasive cervical cancer was also determined. The partial DNA sequences of W13B (MM4), PAP291 (MM7), PAP155 (MM8), and PAP238a (MM9) are most similar to HPV-51, -61, -61, and -34, respectively. Prevalence studies suggest that W13B and PAP238a are cancer-associated, while PAP155 and PAP291 appear to be lower-risk viruses.