Paleopathology of Human Tuberculosis and the Potential Role of Climate

Abstract

Both origin and evolution of tuberculosis and its pathogens (Mycobacterium tuberculosiscomplex) are not fully understood. The paleopathological investigation of human remains offers a unique insight into the molecular evolution and spread including correlative data of the environment. The molecular analysis of material from Egypt (3000–500 BC), Sudan (200–600 AD), Hungary (600–1700 AD), Latvia (1200–1600 AD), and South Germany (1400–1800 AD) urprisingly revealed constantly high frequencies of tuberculosis in all different time periods excluding significant environmental influence on tuberculosis spread. The typing of various mycobacteria strains provides evidence for ancestralM. tuberculosisstrains in Pre- to early Egyptian dynastic material (3500–2650 BC), while typicalM. africanumsignatures were detected in a Middle Kingdom tomb (2050–1650 BC). Samples from the New Kingdom to Late Period (1500–500 BC) indicated modernM. tuberculosisstrains. No evidence was seen forM. bovisin Egyptian material whileM. bovissignatures were first identified in Siberian biomaterial dating 2000 years before present. These results contraindicates the theory thatM. tuberculosisevolved fromM. bovisduring early domestication in the region of the “Fertile Crescent,” but supports the scenario thatM. tuberculosisprobably derived from an ancestral progenitor strain. The environmental influence of this evolutionary scenario deserves continuing intense evaluation.