GENETIC-VARIATION IN FUNCTIONALLY IMPORTANT DOMAINS OF THE BOVINE MTDNA CONTROL REGION

DNA sequences of the mitochondrial control region (CR) of 32 unrelated Austrian cattle were analysed in order to determine the extent of var iability in functionally important domains. Using sequencing of PCR pr oducts, allele-specific PCR (AS-PCR) and primer introduced restriction analysis (PIRA), 43 differences were observed. They included 33 trans itions, five transversions, one deletion and four differences in the n umber of consecutive cytosines. Twenty-three of these polymorphisms ha ve not been reported before. In addition, we analysed all available Eu ropean cattle sequences for this region. The transcriptional start sit es, the conserved sequence block CSB 1 and both binding sites for the mitochondrial transcription factor mtTFA were highly conserved. We fou nd a transition in each of the inter-specifically conserved Mt4 and Mt 5 elements, three nucleotide substitutions in the termination-associat ed sequence TAS-A and six polymorphisms in the conserved sequence bloc k CSB 2 + 3, a region which has been implicated in mitochondrial RNA p rocessing. (C) 1998 Elsevier Science B.V.