TY - JOUR

T1 - More on contamination: the use of asymmetric molecular behavior to identify authentic ancient human DNA.

AU - Malmström, Helena

AU - Svensson, Emma M

AU - Gilbert, M Thomas P

AU - Willerslev, Eske

AU - Götherström, Anders

AU - Holmlund, Gunilla

N1 - Keywords: Animals; Bone and Bones; Cattle; DNA; DNA, Mitochondrial; Dogs; Fossils; Haplotypes; Humans; Polymerase Chain Reaction; Specimen Handling; Tooth

PY - 2007

Y1 - 2007

N2 - Authentication of ancient human DNA results is an exceedingly difficult challenge due to the presence of modern contaminant DNA sequences. Nevertheless, the field of ancient human genetics generates huge scientific and public interest, and thus researchers are rarely discouraged by problems concerning the authenticity of such data. Although several methods have been developed to the purpose of authenticating ancient DNA (aDNA) results, while they are useful in faunal research, most of the methods have proven complicated to apply to ancient human DNA. Here, we investigate in detail the reliability of one of the proposed criteria, that of appropriate molecular behavior. Using real-time polymerase chain reaction (PCR) and pyrosequencing, we have quantified the relative levels of authentic aDNA and contaminant human DNA sequences recovered from archaeological dog and cattle remains. In doing so, we also produce data that describes the efficiency of bleach incubation of bone powder and its relative detrimental effects on contaminant and authentic ancient DNA. We note that bleach treatment is significantly more detrimental to contaminant than to authentic aDNA in the bleached bone powder. Furthermore, we find that there is a substantial increase in the relative proportions of authentic DNA to contaminant DNA as the PCR target fragment size is decreased. We therefore conclude that the degradation pattern in aDNA provides a quantifiable difference between authentic aDNA and modern contamination. This asymmetrical behavior of authentic and contaminant DNA can be used to identify authentic haplotypes in human aDNA studies. Udgivelsesdato: 2007-Apr

AB - Authentication of ancient human DNA results is an exceedingly difficult challenge due to the presence of modern contaminant DNA sequences. Nevertheless, the field of ancient human genetics generates huge scientific and public interest, and thus researchers are rarely discouraged by problems concerning the authenticity of such data. Although several methods have been developed to the purpose of authenticating ancient DNA (aDNA) results, while they are useful in faunal research, most of the methods have proven complicated to apply to ancient human DNA. Here, we investigate in detail the reliability of one of the proposed criteria, that of appropriate molecular behavior. Using real-time polymerase chain reaction (PCR) and pyrosequencing, we have quantified the relative levels of authentic aDNA and contaminant human DNA sequences recovered from archaeological dog and cattle remains. In doing so, we also produce data that describes the efficiency of bleach incubation of bone powder and its relative detrimental effects on contaminant and authentic ancient DNA. We note that bleach treatment is significantly more detrimental to contaminant than to authentic aDNA in the bleached bone powder. Furthermore, we find that there is a substantial increase in the relative proportions of authentic DNA to contaminant DNA as the PCR target fragment size is decreased. We therefore conclude that the degradation pattern in aDNA provides a quantifiable difference between authentic aDNA and modern contamination. This asymmetrical behavior of authentic and contaminant DNA can be used to identify authentic haplotypes in human aDNA studies. Udgivelsesdato: 2007-Apr

U2 - 10.1093/molbev/msm015

DO - 10.1093/molbev/msm015

M3 - Journal article

C2 - 17255122

VL - 24

SP - 998

EP - 1004

JO - Molecular Biology and Evolution

JF - Molecular Biology and Evolution

SN - 0737-4038

IS - 4

ER -