“…Beginning in 1975, a trickle of adenovirus DNA sequence data has by now increased to a continuingflood (Steenbergh et aL, 1975;Arrand & Roberts, 1979;Akusj~irvi & Pettersson, 1979;Herisse et aL, 1980;van Ormondt et aL, 1980). In 1979 the hepatitis B virus genome sequence was published, as deduced from cloned DNA fragments (Charnay et al, 1979;Pasek et al, 1979;Valenzuela et al, 1979). There are now appearing fairly large amounts of sequence data on retroviruses, as DNAs (Czernilofsky et aL, 1980;Sutcliffe et aL, 1980).…”