April 2005 - Volume 7 - Number 2

Short Communication

Interlaboratory Study on Bone Extraction for Mitochondrial DNA Analysis

Scientific Working Group on DNA Analysis Methods Mitochondrial DNA Subcommittee

With the implementation of the National Missing Persons DNA Database, the forensic DNA analysis of bone evidence remains continues to increase. Because the DNA found in bone evidence is frequently limited and/or degraded, mitochondrial DNA (mtDNA) analysis is often the analysis method of choice.

In addition to government and commercial laboratories currently conducting mtDNA analysis, several new forensic mtDNA laboratories are completing internal validation studies and are preparing to begin casework. It is anticipated that a substantial portion of this casework will deal with remains from missing persons. However, the availability of human bones for training purposes is limited. Furthermore, to date, no proficiency test is available using bones as evidentiary material.

The Mitochondrial DNA Subcommittee of the Scientific Working Group on DNA Analysis Methods is assembling an interlaboratory study comparing the extraction methodologies and sequencing results obtained from a single source of bone sample. The study is designed so that similar bones (i.e., toe bones) or sections of a long bone (i.e., femur) will be obtained from a single donor and distributed to the participating laboratories. Extraction, amplification, and sequencing of the resulting bone DNA will proceed according to the laboratories’ standard protocols. At a minimum, submitted results will include sequencing of HV1 and HV2. In addition, sequence from mtDNA mini-primer sets, autosomal STR, Y STR, as well as mtDNA coding region and control region SNP data will be evaluated, if obtainable. All raw data generated during sample processing will be submitted.

Comparison of the results and extraction methodologies may highlight differences in methodologies that can be improved to give greater yield of high quality extracted DNA and/or amplified product. In addition, it is expected that this exercise will lend assurance to the field that subtle differences in amplification and sequencing protocols do not lead to differing mtDNA profiles.

In order to provide the most benefit to the forensic mtDNA community, priority will be given to government and commercial forensic laboratories in the United States and abroad currently conducting mtDNA testing. In addition, laboratories that anticipate conducting mtDNA testing in the near future are welcome to participate. Academic laboratories are also encouraged to participate, if sufficient bone material is available.

Interested laboratory directors or managers may complete and fax the form to 703-632-7573 (Attention: Connie Fisher) by June 1, 2005, to be considered for participation in the study. Because the supply of bone sample may be limited, participants will first be screened based on the submitted form. Prior to release of the study bone sample, participants must submit a written protocol and agree to provide results within three months of sample receipt.