Leprosy results from infection with Mycobacterium leprae bacteria, and leads to nerve damage and mutilation. Leprosy, seen in Europe until the 16th century, is still common in the developing world. Johannes Krause at the University of Tübingen, Germany, obtained nearly complete genomes of M. leprae from 11th- to 14th-century European skeletal remains and recent biopsies worldwide. DNA from ancient M. leprae was astonishingly preserved, likely because the bacteria’s thick waxy cell wall protects DNA from environmental destruction. Sequence comparisons revealed little genomic changes among M. leprae strains during the past 1000 years, and showed that leprosy in the Americas originated in Europe.
Did you know? Armadillos, the only animals besides humans known to carry leprosy, can transmit the disease to humans.