Abstract
Around 11000 years ago the first domesticated mammals emerged in the Fertile Crescent.
Over time, these animals spread to fertile regions both to the east and west of their domestic
centre of origin. By 6000 BP, animal husbandry had reached Northern Europe, and it had
become established in Norway by circa 4100 BP. Domestic sheep (Ovis aries) was probably
among the first domestic species to be introduced to Norway and by the Middle Ages (476-
1453 AD) animal husbandry and sheep herding was well established here. Not much is known
about the composition of domestic sheep in mediaeval Norway, but it has been suggested that
new breeds were introduced from other countries as this was a time of increasing trade.
Four different mitochondrial DNA (mtDNA) haplogroups, known as A, B, C and D,
have been observed in domestic sheep, of which mtDNA haplogroup A and B are found in
Europe. In this study I analysed genetic data obtained from sheep bones excavated from
archaeological sites (Oslo, Bergen and Trondheim) in Norway dated to the Middle Ages (476-
1453 AD). I also included a bone sample dated to the Viking Age (800-1066 AD) to see if any
genetic variation could be obtained from an older sample. I implemented methods for
extracting ancient mtDNA from bones, and aimed to produce reliable extracts that could be
authenticated as mediaeval sheep DNA. Authentic mtDNA sequences of mediaeval domestic
sheep could provide information that would help answer questions regarding the trading
history and composition of breeds at different geographical regions in mediaeval Norway.
Sheep extracts were amplified with sheep specific primers and cytochrome b primers
simultaneously. Negative and positive controls, as well as samples of different species were
included in the amplifications. PCR amplifications visualised on electrophoresis agarose gels
could exclude human and cross-contamination of sheep by the nature of the controls. This
suggested that the genetic data were authentic. Of 70 domestic sheep samples, 16 were
successfully sequenced, including one from the Viking Age. Two mtDNA haplogroups were
observed: A and B. One specimen from Trondheim was allocated to haplogroup A, whereas
the remaining samples were haplogroup B. The 16 sequences used in the phylogenetic
analyses were short (88 bp), and thus not informative enough to settle questions regarding the
trade and composition of breeds in mediaeval Norway. However, it could be concluded that
the sheep sequences were authentic, and that two mtDNA sheep lineages were present in
Norway in the Middle Ages.