Submitted to: DNA Sequence
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 7, 2003
Publication Date: August 1, 2003
Citation: Waldbieser, G.C., Bilodeau, A.L., Nonneman, D.J. 2003. Complete sequence and characterization of the channel catfish mitochondrial genome. DNA Sequence 14:265-277. Interpretive Summary: Identification of catfish strains and families is difficult due to the similar physical characteristics of all channel catfish. The complete DNA sequence was determined for the entire mitochondrial genome of channel catfish, Ictalurus punctatus, using high-throughput genomic analysis. The DNA sequences of two mitochondrial genes, cytochrome c oxidase subunit 1 and cytochrome B, were also determined from other catfish species. Sequence comparisons supported current taxonomic separation of catfish species with the order Siluriformes. Analysis of one region, termed the D-loop, in commercial and research populations revealed 34 different sequence patterns which will be useful for fingerprinting catfish families and strains.
Technical Abstract: The channel catfish mitochondrial genome was amplified in 6 overlapping fragments and completely sequenced to reveal a contig of 16497 bp. Gene structure and order was identical to that of other fish and mammalian species. Protein sequence comparisons of cytochrome c oxidase subunit 1 and cytochrome B demonstrated a high degree of sequence similarity between channel catfish and other ictalurids. Phylogenetic analysis demonstrated a separation of the genera Ictalurus, Pylodictis, and Ameiurus. Analysis of the D-loop region sequence in 139 fish revealed 30 polymorphic sites, and 34 haplotypes were identified in channel catfish populations. Sequence analysis indicated a clustering of different haplotypes within commercial farms and within a research strain. Mitochondrial DNA polymorphism will provide a useful tool for identification and management of channel catfish.