This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Introduction to Archaeology: Class 15 More bioarchaeology: DNA for relatedness and migration Copyright Bruce Owen 2002 Ancient DNA studies DNA is sometimes preserved in soft tissues, hair, or well-preserved bone but this is so mostly in relatively recent material or material from especially good preservation conditions artificial or natural mummies bone that was not exposed to the elements and was buried in a fairly dry or frozen context The DNA is usually broken into short segments; the less well preserved, the shorter the pieces longer pieces are more likely to include complete nucleotide base sequences that can be used for matching or contrasting with other samples very small amounts can be copied or "multiplied" into usable quantities using PCR Polymerase Chain Reaction: a test-tube method that essentially imitates the natural process of replication of DNA but all the DNA in the test tube will get multiplied, including any from microscopic bits of skin, finger oils, saliva droplets, etc. of the lab technician, the excavator, etc. so control of contamination is crucial ideally, all the people ever associated with the sample provide DNA samples and the "ancient" DNA is first checked against these to make sure that none of it comes from the modern people involved DNA studies often use mtDNA found in mitochondria, not nuclei of cells there are many mitochondria per cell, vs. only one copy of each chromosome in the nucleus so there is a lot more mtDNA to start with this improves the odds of getting usable mtDNA from an ancient sample inherited only from the mother no recombination due to sexual reproduction so offspring's DNA is theoretically identical to its mother's this allows for reconstructing or confirming family relationships, as in Thomas's example of the bodies of Czar Nicholas II and his family so the only changes are from the occasional error in natural DNA replication these build up slowly over generations so people who share a female ancestor in their maternal descent line (mother-...
View Full Document
This note was uploaded on 03/02/2012 for the course ANTHRO 324 taught by Professor Bruceowen during the Fall '02 term at Sonoma.
- Fall '02