RT Journal Article SR Electronic(1) A1 Eschle, Daniel A1 Dürst, Matthias A1 ter Meulen, Jan A1 Luande, Jeff A1 Eberhardt, Hans C. A1 Pawlita, Michael A1 Gissmann, LutzYR 1992 T1 Geographical dependence of sequence variation in the E7 gene of human papillomavirus type 16 JF Journal of General Virology, VO 73 IS 7 SP 1829 OP 1832 DO https://doi.org/10.1099/0022-1317-73-7-1829 PB Microbiology Society, SN 1465-2099, AB We have determined nucleotide sequences of the E7 open reading frame (ORF) of human papillomavirus type 16 (HPV-16) isolates obtained from 32 genital tumours and two HPV-16-transformed human keratinocyte cell lines. In comparison to the prototype HPV-16 isolated from a German cervical cancer biopsy, no sequence variations were noticed in either the two cell lines or the 10 biopsies that were obtained from German patients. In contrast only three of 22 (13.6%) of Tanzanian isolates showed the prototype sequence. In 18 of these biopsies two alterations (T to C and T to G) not affecting the amino acid sequence were found within the HPV-16 E7 ORF (nucleotide positions 789 and 795) but eight of these isolates contained an additional change (nucleotide position 647) coding for serine instead of asparagine (amino acid position 29). One tumour harbours HPV-16 DNA with a mutation (C to T) at nucleotide 790 changing the E7 amino acid sequence (arginine to cysteine) at position 76. Our findings suggest that clustering of E7 sequence variants may occur in different geographical regions of the world., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/0022-1317-73-7-1829