Evaluation of nuclear DNA from rootless hair for forensic purposes

Many potential forensic samples are not amenable to DNA-based analysis because they contain too little DNA, or the DNA is too degraded. We propose a method for such samples, like single hair shafts, that allows forensic genetic genealogy. Following on our recent real-world successes in this area, we propose to collect data that will provide important parameters for amount of samples and depth of sequencing for reliable genotype calling. We further propose to develop a computational pipeline that not only delivers accurate genotype files but also reports quality control metrics and a determination of whether a sample is from a single source or is a mixture. Finally, we propose to develop a hybridization capture approach to reduce the overall cost of this approach. Our analysis will include characterization of DNA content in head and pubic hair, efficiency of library generation, and reliability of genotype calls as a function of depth of sequencing. We will make our results available via peer-reviewed publications and through presentation at the International Symposium on Human Identification in 2021 and 2022. We anticipate that the data and tools developed will help guide parameters for responsible and effective use of forensic genetic genealogy for difficult samples. The DNA sequence data we generate will be made available to the research community via deposition in the National Center for Biotechnology Information’s Sequence Read Archive. Using this approach, we have repeatedly been able to generate investigative leads from data extracted from a single, decades-old rootless human hair. We hope to provide this power to the general forensics community along with a thorough evaluation of its reliability. Note: This project contains a research and/or development component, as defined in applicable law, and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14). CA/NCF