Mitochondrial DNA sequence and gene organization in the Australian Blacklip Abalone Haliotis rubra (Leach)

The complete mitochondrial DNA of the blacklip abalone <i>Haliotis rubra</i> (Gastropoda: Mollusca) was cloned and 16,907 base pairs were sequenced. The sequence represents an estimated 99.85% of the mitochondrial genome, and contains 2 ribosomal RNA, 22 transfer RNA, and 13 protein-coding genes found in other metazoan mtDNA. An AT tandem repeat and a possible C-rich domain within the putative control region could not be fully sequenced. The <i>H. rubra</i> mtDNA gene order is novel for mollusks, separated from the black chiton <i>Katharina tunicata</i> by the individual translocations of 3 tRNAs. Compared with other mtDNA regions, sequences from the <i>ATP8, NAD2, NAD4L, NAD6</i>, and <i>12S rRNA</i> genes, as well as the control region, are the most variable among representatives from Mollusca, Arthropoda, and Rhynchonelliformea, with similar mtDNA arrangements to <i>H. rubra.</i> These sequences are being evaluated as genetic markers within commercially important <i>Haliotis</i> species, and some applications and considerations for their use are discussed. <br>