Typing of human papillomaviruses in cervical carcinoma biopsies from Cape Town

Sixty-eight cervical carcinoma biopsies from women at Groote Schuur hospital in Cape Town were screened for human papillomavirus (HPV) DNA by polymerase chain reaction (PCR) amplification with subsequent typing by hybridisation with specific oligonucleotides. Amplified DNAs which hybridised with the HPV group-specific oligonucleotide probes, but with none of the type-specific probes, were categorized as unclassified HPV types. Eighty-one percent of samples were HPV positive and the following distribution and types were detected: 46% HPV 16, 1.5% HPV 18, 6% HPV 31, 6% HPV 33, 1.5% HPV 45, and 25% unclassified HPVs. Four of the tumours had detectable dual infections with the following combinations of HPVs: HPV31/HPV33; HPV16/HPV33; HPV18/HPV16; HPV45/HPV33. Tumour DNA from the 17 PCR unclassified HPVs was analysed by Southern blotting and gave the following results: 11 were negative, 4 were positive on hybridisation but could not be typed (unclassified HPV), 1 was HPV 16, and 1 resembled the HPV 16 "variant" described previously [Williamson et al. (1989): Journal of Medical Virology 28:146-149]. Only 2 of 13 samples that were negative for HPV by PCR were positive for unclassified HPVs by Southern blot analysis. Sequencing of a PCR product revealed that one of the unclassified HPVs was HPV 52. This is the first record of HPV 52 and HPV 45 in Africa.