Recombinam DNA technologies offer new methods of detecting animal diversity at various levels. DNA »fingerprinting« using cloned repetitive sequences can be used to distinguish between individuals within breeds and may thus be used for paternity testing (Jeffreys et al. 1985). The forensic value of evidence of this kind has given guarded approval by the UK Immigration Advisory Service in its annual report (Nature 1987). At the between-species level labeled total genomic DNA was used by Durnam et al. (1985) as probe in an in situ hybridization for speciesverification of chromosomal materials in human-rodent hybrid cell lines, and we recently described the use of 3H-labeled genomic pig DNA probe for detection af swine chromosomes in swine-hamster hybrid cell lines (Thomsen & Christensen 1986).