No sequence variation in part of the hexon and the fibre genes of adenovirus 8 isolated from patients with conjunctivitis or epidemic keratoconjunctivitis (EKC) in Norway during

Background/Aims—Several local epidemics of keratoconjunctivitis/conjunctivitis caused by adenovirus type 8 (Ad8) occurred in Norway from August 1995 to May 1996. A smaller epidemic occurred in 1992. The Ad8 hexon forms the surface of the virion and contains the hypervariable regions loop I1 and loop I2. The fibre mediates the primary contact with cells. Sequence variation in hexon and fibre genes might play an important role in the pathogenicity of adenoviruses. The aim of this study was to investigate the genetic variability at the hexon and fibre genes in 26 strains of Ad8 isolated from 1989 to 1996. Methods—The genetic variability of 26 strains of Ad8 isolated from 1989 to 1996 was studied by sequencing part of the hexon and fibre genes. The Ad8 sequences were compared with each other and with two Ad8 strains from the EMBL database. In addition, 14 of the 26 isolates were subjected to restriction endonuclease analysis. Results—No significant sequence variation was seen during the six year period. Conclusion—The Ad8 strains causing epidemics of keratoconjunctivitis/ conjunctivitis in Norway are genetically stable. (J Clin Pathol 2001;54:558–561)