October 27th, 2011

Black Death DNA Discovered

The teeth of four plague victims uncovered in east London have yielded fragments of DNA that is 700 years old, and thought to be that of the bug which causes the Bubonic Plague, otherwise known as the “Black Death”. Scientists have managed to reconstruct the complete genetic code of the Yersinia pestis bug, which killed up to 50% of the population of Europe (around 100 million) in the five years between 1347 and 1351. It is the very first time that researchers have had success in successfully drafting the genome of any pathogen or other disease causing agent from ancient times. Yes it’s amazing, but a little scary too, don’t you think, especially since they consider the particular strain they reconstructed as the mother of all modern bacteria associated with the Bubonic Plague.

The discovery definitely represents the leaps and bounds by which the science of genetic engineering and DNA manipulation has grown though. The discovery could lead to important insights into the evolution of human pathogens, enabling scientists to develop preventative vaccines or effective cures for a number of pathogen related illnesses. Bubonic Plague itself continues to cause around 2,000 deaths per year around the world. Many of our ancestors have succumbed to such diseases over the years, and the thought that future genealogists may not find their ancestors amongst the victims of such illnesses is indeed a refreshing one!

Over the last 100 years infant mortality has drastically in the Western world, due largely to the advent of antibiotics and vaccination. However as sickness and death from infectious disease has lessened the toll from genetic disease has become significantly greater.  At present about 20% of the total of infant deaths in developed countries are due to the inheritance of single-gene disorders, something that could be eradicated due to discoveries and research like the above.

DNA Genealogy News

On the subject of genealogy, researchers continue to discover new and interesting genealogy related attributes of DNA. Y-chromosome and mtDNA studies in particular continue to develop the science of the human genome.  Recent studies have revealed that the deepest ancestry of Japan actually occurs in Siberia. The study of Japan’s prehistoric Jomon people revealed similar mtDNA haplogroups to ancient Siberian [peoples. Studies like this cast light on worldwide ancient immigration patterns and civilization developments, but at the same time make it easier for genealogists to discover their ancient roots.

An interesting issue was raise recently at the Personal Genomes meeting at Cold Spring Harbor Laboratory, a genetic research facility in New York. The question was raised whether a researcher should inform a subject if they find something unexpected or abnormal during the testing of a person’s DNA. It seems there are no set of established ethics when it comes to revealing bad news to DNA test subjects, though United States Law prohibits researchers from revealing anything to patients until the results of been double checked by another certified lab, which most researchers then do. Unfortunately because of the time period involved, subjects don’t usually find out about their condition until the particular study has been published. Some scientists argue that the problem can be eliminated by having the work done only in certified labs from the beginning, so that subjects can receive any news immediately. The debate is ongoing, but what do you think about the subject? Feel free to post your thoughts below.