Mitochondrial DNA preservation across 3000-year-old northern fur seal ribs is not related to bone density: Implications for forensic investigations.
While recent forensic research has focused on determining which skeletal elements are superior in their preservation of DNA over the long term, little focus has been placed on measuring intra-element variation. Moreover, there is a general belief that dense (cortical) bone material will contain better-preserved DNA than does spongy (cancellous) bone. To address these ideas, quantitative PCR was used to estimate the degree of mitochondrial DNA (mtDNA) preservation variance across sections of 19 northern fur seal ribs (Callorhinus ursinus) that date to ∼3000 years before present. Further, we developed a measure called the "density index" that was used to gauge the relative densities of the rib sections studied here to determine if density was an appropriate predictor of preservation. The average preservation among the samples was significantly different (ANOVA, p=1.9×10(-9)) with only 15% of the total variance observed within samples. However, 12 of the 19 specimens (∼63.2%) exhibited at least an order of magnitude difference in mtDNA preservation across the whole. Regression of the amount of mtDNA extracted per gram of bone material against the density index of the bone from which it was extracted demonstrates no relationship between these variables (R(2)=0.03, p=0.28).
School of Biological Sciences, Washington State University, Pullman, WA 99164, USA; Department of Anthropology, Washington State University, Pullman, WA 99164, USA; Department of Biological and Health Sciences, Madonna University, Livonia, MI 48150, USA.
Jodi Lynn
JL
Barta
School of Biological Sciences, Washington State University, Pullman, WA 99164, USA; Department of Anthropology, Washington State University, Pullman, WA 99164, USA; Department of Anthropology, University of California-Santa Barbara, Santa Barbara, CA 93106, USA.
Cara
C
Monroe
Pacific Identifications Inc., 6011 Oldfield Road, R.R. #3, Victoria, BC V9E 2J4, Canada; Department of Anthropology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada.
Susan J
SJ
Crockford
School of Biological Sciences, Washington State University, Pullman, WA 99164, USA; Department of Anthropology, Washington State University, Pullman, WA 99164, USA. Electronic address: bmkemp@wsu.edu.
Brian M
BM
Kemp
D000818:Animals; D015519:Bone Density; D004272:DNA, Mitochondrial / Q000235:genetics* / Q000302:isolation & purification*; D018732:Forensic Anthropology; D046069:Fur Seals / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012272:Ribs / Q000737:chemistry*
D004272:DNA, Mitochondrial
Ancient DNA; Bone density; Quantitative PCR