We examined the genomic diversity of human papillomavirus type 6 (HPV-6) and HPV-11 isolates from different parts of the world by comparing the nucleotide sequences of part of the long control region of three reference clones and 62 HPV-6 and 40 HPV-11 isolates from Africa, Europe, Asia, and North and South America. The genomic sequence of the HPV-6b reference type had to be amended by inclusion of a 94-bp segment, which is also present with minor differences in HPV-6a. Aside from two small inserts typical of all variants related to HPV-6a and three inserts found in HPV-11 variants, no major alterations to the size of the long control regions of these viruses were observed. This corrects the previous impression that these two HPV types are highly polymorphic. Altogether, 19 HPV-6 and 10 HPV-11 variant genomes could be distinguished, and most of the differences were due to point substitutions. The variants of either type were continuously connected in phylogenetic trees rather than clustered separately into subtype groups. Thirteen mutations, namely, the two HPV-6a inserts and 11 substitutions in HPV-6 or HPV-11 variants, reduced the dissimilarity between the types, but they bridged only a small fraction of the genetic distance between the two types. Genomes more obviously intermediate between HPV-6 and HPV-11 were not found and probably do not exist any more. A single HPV-11 variant was found in Africa, but otherwise, no significant correlations of HPV-6 or HPV-11 variants with geography or ethnicity of the patient cohort were found. Functional analysis of diverse enhancer variants showed activities that differed two-to threefold, and it must be considered that transcriptional differences may alter the biology or pathology of these viruses. Similar variants were found in lesions from anatomically different sites and in both benign and malignant lesions.

Deoxyspergualin achieved a high rate of disease remission and permitted prednisolone reduction in refractory or relapsing Wegener's granulomatosis. Adverse events were common but rarely led to treatment discontinuation.

India has one of the world's highest incidences of oral cancer. It is believed that the widespread habit of betel quid chewing is an important risk factor as it exposes the oral mucosa to known carcinogens. It also induces physical abrasions, which may create mitogenic environments during wound healing as gateways for infections. A recent study from our laboratories identified human papillomavirus (

In patients with refractory Wegener's granulomatosis, prolonged treatment with DSG seems safe and successful.