Osteological and molecular identification of brucellosis in ancient Butrint, Albania

Abstract

Ancient skeletal remains can harbor unique information about past civilizations at both the morphological and molecular levels. For instance, a number of diseases manifest in bone, some of which have been confirmed through DNA analysis, verifying their presence in ancient populations. In this study, anthropological analysis of skeletal remains from the ancient Albanian city of Butrint identified individuals with severe circular lytic lesions on their thoracic and lumbar vertebrae. Differential diagnosis suggested that the lesions resulted from pathologies known to affect these skeletal regions, such as tuberculosis (TB) or brucellosis. Relevant bones of two adolescent males from the 10th to 13th century AD that displayed the lesions, along with unaffected individuals, were collected in the field. Genetic screening of the skeletal samples for TB was repeatedly negative, thus additional testing for Brucella spp.-bacteria of livestock and the causative agent of brucellosis in humans-was conducted. Two Brucella DNA markers, the IS6501 insertion element and Bcsp31 gene, amplified from the affected vertebrae and/or ribs, whereas all unaffected individuals and control samples were negative. Subsequent DNA sequencing confirmed the presence of the brucellar IS6501 insertion element. On the basis of the skeletal lesions, negative tests for TB, and positive Brucella findings, we report a confirmed occurrence of brucellosis in archaeologically recovered human bone. These findings suggest that brucellosis has been endemic to the area since at least the Middle Ages.