Unfortunately, you're a bit late. The mitochondrial genomes of cartiliginous fishes have been done for some time, and they're just what we evil evos thought they would be. Sorry.
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=10051614
No, not late. Brand new, as in, so new that the article for this thread is crowing about the new conclusion.
What hasn't been examined yet, keyword: "yet", is whether the tuna and shark, which we now know share remarkably similar (perhaps even identical) tendons and muscles, likewise share identical DNA instruction set subroutines at any significant level.
If such identical programming code subroutines exist in tuna and sharks but do not exist in intermediate species in between, then we would have evidence of genetic code skipping that would falsify Evolutionary Theory.
We aren't there yet (that keyword again), but the article for this thread certainly shows that we are on a collision course for that potential scientific destination.
No doubt that open potential frightens you. You should therefore post some messages ridiculing the whole concept of examining literal base-pair sequences, and otherwise attempt to derail this quest. Who knows, it might even make you feel better; at least until the truth finally comes out...