Genetic Variation in Captive Koalas (Phascolarctos cinereus): Parentage Determination and Individual Identi®cation E. V. Fowler, 1,5 B. A. Houlden, 2,3 W. B. Sherwin, 3 P. Hoeben, 1,4 and P. Timms 1 Received 3 Dec. 1997ÐFinal 15 Apr. 1998 Highly repeatable randomly ampli®ed polymorphic DNA (RAPD) markers were developed for parentage studies in the koala (Phascolarctos cinereus). Of the 25 RAPD primers screened, 5 (20.0%) produced 32 repeatable polymorphic RAPD bands (average/primer 5 6.4 6 4.2). A high level of polymorphism was observed for each group of koalas (Featherdale, 71.9%; Lone Pine, 84.4%). All 25 koalas could be uniquely identi®ed using either RAPD or microsatellite markers. Of the 32 RAPD markers generated in koalas, 25 were informative for parentage analyses. These RAPD markers successfully determined both parents to three offspring and a male parent to a fourth offspring. Paternity analysis (where the female parent is known) succeeded in assigning the correct male parent to seven offspring. Our RAPD±PCR method generates informative genetic markers that are useful for parentage determination and individual identi®cation of captive koalas. This would provide genetic analysis to zoos and wildlife parks as a low-cost alternative to the more expensive microsatellite markers. KEY WORDS: RAPD pro®ling; parentage; paternity; identi®cation; Koala; Phascolarctos cinereus. INTRODUCTION The ability to determine familial relationships among a particular group of individuals is important for their conservation and management, although this 1 Centre for Molecular Biotechnology, School of Life Science, Queensland University of Technology, Brisbane, QLD 4001 Australia. 2 Taronga Zoo, Mosman, NSW 2088, Australia. 3 School of Biological Science, University of New South Wales, Kensington, NSW 2052, Australia. 4 Present address: W3audit.com, Boerlagelaan 1, 1421 TX Uithoorn, The Netherlands. 5 To whom correspondence should be addressed at ForBio Research Pty. Ltd., P.O. Box 1729, Toowong, Queensland 4066, Australia. Fax: 161-7-3870 5777. Biochemical Genetics, Vol. 36, Nos. 5/6, 1998 193 0006-2928/98/0600-01 93$15.00/0 r 1998 Plenum Publishing Corporation