Veterinary Parasitology 112 (2003) 197–201 Molecular differentiation of Hypoderma bovis and Hypoderma lineatum (Diptera, Oestridae) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) Domenico Otranto a,∗ , Donato Traversa b , Elvira Tarsitano a , Jamie Stevens c a Faculty of Veterinary Medicine, University of Bari, Strada Provinciale per Casamassima Km. 3, 70010 Valenzano, Bari, Italy b Faculty of Veterinary Medicine, University of Teramo, Piazza Aldo Moro 45, 64100 Teramo, Italy c School of Biological Sciences, University of Exeter, Prince of Wales Road, Exeter EX4 4PS, UK Received 16 July 2002; received in revised form 24 October 2002; accepted 11 November 2002 Abstract The most variable region of the cytochrome oxidase I (COI) gene of Hypoderma bovis 1 and Hypoderma lineatum 2 (Diptera, Oestridae) was amplified by PCR and the amplicons were se- quenced and analysed. PCR products were digested with three restriction enzymes, namely BfaI, Hinf I and TaqI, providing informative profiles. H. bovis and H. lineatum sequences revealed an inter-specific variation rate of 8.5%, and an intra-specific variation rate of 0.87 and 0.29%, respec- tively. The results showed that the COI gene region examined was useful for the differentiation of H. bovis and H. lineatum and that a PCR-RFLP assay is a practical tool for their identifica- tion, offering additional diagnostic and epidemiological instruments for the study of cattle grub infestation. © 2002 Elsevier Science B.V. All rights reserved. Keywords: Hypoderma bovis; Hypoderma lineatum; Myiasis; PCR-RFLP; Cytochrome oxidase I; Mitochondrial DNA ∗ Corresponding author. Tel.: +39-80-4679839; fax: +39-80-4679835. E-mail address: d.otranto@veterinaria.uniba.it (D. Otranto). 1 Accession number: AF497761. 2 Accession number: AF497762. 0304-4017/02/$ – see front matter © 2002 Elsevier Science B.V. All rights reserved. doi:10.1016/S0304-4017(02)00418-1