CRL team extracts ancient DNA from individual who died 85 years ago.

By Dr. Latifa Jackson

   Over the past year, the Howard University W. Montague Cobb Research Lab (CRL) has been developing protocols and collaborations to analyze the ancient DNA present in the skeletal remains from those individuals in the collection. The collection contains individuals who were born between 1860 and 1959, with 699 individuals available for possible analysis. Our desire to attain sequence data for these individuals will help to increase our understandings of the genetics of individuals living in the late 19th and early 20th centuries.  We began our work by forming a collaboration with the Centre for GeoGenetic  at the University of Copenhagen. From this collaboration we learned their protocols in extracting ancient DNA and ways to address possible methodological issues associated with trying to capture human ancient DNA. While they worked on a subset of samples from another ancient DNA collection, the CRL took these technologies back to Howard University to run a pilot study to determine the ancient DNA yield in a sample individual (CC672) from the CRL collection. This individual lived 85 years ago. In order to have maximum preservation of the collection, we chose to extract DNA from the upper molars which were still imbedded in the skull. These were carefully removed, scraped and the remnants of tissue structures were scraped off. We used phenol chloroform, Qiagen and Oragene extraction methods. Quantification of the samples showed DNA was present in all of these methods; however the phenol chloroform delivered the highest DNA concentrations and will be the methodology used in the future to extract DNA from the skeletal collection. We are currently studying methods available to increase the capture of human specific DNA in these samples since the DNA was shown to still be quite degraded. DNA degradation is a common result of long term DNA presence. We will continue to work to bring ancient DNA sequencing to the CRL samples in order to gain insights into their genetics and associated genetic disease phenotype predispositions. We are excited by our preliminary findings and hope to start DNA extractions of these unique historical skeletal resources at Howard University. ****