The Swedish Museum's specimen [NRM 566599] is an eviscerated adult female preserved in ethanol.  The specimen was acquired by Stockholm University on the 30th April 1893 and transferred to the Swedish Museum of Natural History in the early 1970s (ITSD, 2013).  Before entering the university's collection, the thylacine had been on display at the London Zoo from the 14th November 1884 until the 2nd April 1893.  It had been snared at Bowood (Tasmania) in August 1883 by Mr. A. W. Brewer, and was purchased prior to its sale to the London Zoo by Dr. A. Bingham Crowther of Bridport (Tasmania).  The specimen is the finest preserved thylacine in existence.     The team extracted DNA from small samples of the hair of both specimens and then sequenced independent copies of each region of the DNA molecule from the many different fragments of DNA in the hairs.  The high fidelity of the team's results were assured by independently determining each position in the sequences an average of 50 times.     The team sequenced all the DNA in the hair samples from the two thylacine specimens, including mitochondrial DNA, which is the focus of the genome research paper, and nuclear DNA, which the team plans to analyse in future work.     Schuster states: "This study, in which we sequenced the complete mitochondrial genome of the thylacine species, also shows that it is feasible to sequence its complete nuclear genome".

. Thylacine specimen 2 (GenBank accession number: FJ515781).  Photo: International Thylacine Specimen Database, 5th Revision 2013.  Courtesy: Swedish Museum of Natural History, (Stockholm).

    The genome team state: "There has been an ongoing debate concerning the precise position of the Tasmanian tiger within the marsupial family tree.  Early studies of bones and other morphological traits grouped the thylacine with South American carnivorous marsupials.  Later morphological studies placed it among Australian marsupials, possibly near the family Dasyuridae, a group that includes the Tasmanian devil and quolls.  The 1990's saw the advent of the polymerase chain reaction and special methods for recovering DNA from museum specimens.  These early molecular studies obtained only very short fragments of the thylacine's mitochondrial DNA from museum specimens, but confirmed a close relationship near the devil and its relatives, and a slightly more distant relationship to the numbat (family Myrmecobidae).  We have determined two thylacine mitochondrial genomes, in addition to a modest fraction of the thylacine's nuclear genome.  These considerably longer DNA sequences now firmly place the thylacine in the mammalian family tree, not as a close relative of the Tasmanian devil, but separated by nearly 40 million years from the devil and the numbat".

    Miller reports: "The two thylacine sequences were extremely similar to each other, with only 5 differences in 15,492 nucleotides".  Nucleotides are the molecules that form the basic building blocks of RNA and DNA.  They are organic compounds composed of a nitrogenous base, a sugar and a phosphate group.  The similarity in the thylacine sequences is indicative of a low level of genetic diversity within the species. 

    The genome team's research revealed that two previous DNA sequences in public databases, both labelled as thylacine mitochondrial genes, were incorrect.  Schuster states: "Our Smithsonian specimen was the male offspring of the female animal named as the source of the earlier data, so the mitochondrial sequences, which are inherited only from the mother, should have been identical, but our analyses showed they are over 10 percent different".