Archival, paleopathological and aDNA-based techniques in leprosy research and the case of Father Petrus Donders at the Leprosarium 'Batavia', Suriname.

OBJECTIVE: We assessed whether Petrus Donders (died 1887), a Dutch priest who for 27 years cared for people with leprosy in the leprosarium Batavia, Suriname, had evidence of Mycobacterium (M.) leprae infection. A positive finding of M. leprae ancient (a)DNA would contribute to the origin of leprosy in Suriname. MATERIALS: Skeletal remains of Father Petrus Donders; two additional skeletons excavated from the Batavia cemetery were used as controls. METHODS: Archival research, paleopathological evaluation and aDNA-based testing of skeletal remains. RESULTS: Neither archives nor inspection of Donders skeletal remains revealed evidence of leprosy, and aDNA-based testing for M. leprae was negative. We detected M. leprae aDNA by RLEP PCR in one control skeleton, which also displayed pathological lesions compatible with leprosy. The M. leprae aDNA was genotyped by Sanger sequencing as SNP type 4; the skeleton displayed mitochondrial haplogroup L3. CONCLUSION: We found no evidence that Donders contracted leprosy despite years of intense leprosy contact, but we successfully isolated an archaeological M. leprae aDNA sample from a control skeleton from South America. SIGNIFICANCE: We successfully genotyped recovered aDNA to a M. leprae strain that likely originated in West Africa. The detected human mitochondrial haplogroup L3 is also associated with this geographical region. This suggests that slave trade contributed to leprosy in Suriname. LIMITATIONS: A limited number of skeletons was examined. SUGGESTIONS FOR FURTHER RESEARCH: Broader review of skeletal collections is advised to expand on diversity of the M. leprae aDNA database.

Ancient genomes reveal a high diversity of Mycobacterium leprae in medieval Europe.

Studying ancient DNA allows us to retrace the evolutionary history of human pathogens, such as Mycobacterium leprae, the main causative agent of leprosy. Leprosy is one of the oldest recorded and most stigmatizing diseases in human history. The disease was prevalent in Europe until the 16th century and is still endemic in many countries with over 200,000 new cases reported annually. Previous worldwide studies on modern and European medieval M. leprae genomes revealed that they cluster into several distinct branches of which two were present in medieval Northwestern Europe. In this study, we analyzed 10 new medieval M. leprae genomes including the so far oldest M. leprae genome from one of the earliest known cases of leprosy in the United Kingdom-a skeleton from the Great Chesterford cemetery with a calibrated age of 415-545 C.E. This dataset provides a genetic time transect of M. leprae diversity in Europe over the past 1500 years. We find M. leprae strains from four distinct branches to be present in the Early Medieval Period, and strains from three different branches were detected within a single cemetery from the High Medieval Period. Altogether these findings suggest a higher genetic diversity of M. leprae strains in medieval Europe at various time points than previously assumed. The resulting more complex picture of the past phylogeography of leprosy in Europe impacts current phylogeographical models of M. leprae dissemination. It suggests alternative models for the past spread of leprosy such as a wide spread prevalence of strains from different branches in Eurasia already in Antiquity or maybe even an origin in Western Eurasia. Furthermore, these results highlight how studying ancient M. leprae strains improves understanding the history of leprosy worldwide.

First genetic evidence of leprosy in early medieval Austria.

Leprosy used to be a widespread, dreaded disease in Europe during the middle ages, and it still remains an important health problem in some parts of the world today. Herein, we present data on the earliest 'Austrian' (an adult female from the early medieval period) proven to have suffered from leprosy. Manifestations of the disease were first identified during a systematic screening of pathological changes in skeletons recovered from an archaeological site in Pottenbrunn (Lower Austria). In the present study, DNA extracts from selected cranial and postcranial bone samples were investigated using polymerase chain reaction primers specific to the Mycobacterium leprae (M. leprae) repetitive element (RLEP). M. leprae traces were detected in extracts from nasal and palatine bones. Sequence analysis of informative polymorphic sites supports previous reports indicating that European M. leprae strains fall into single nucleotide polymorphism group 3. In summary, these findings put Austria on the map of confirmed leprosy cases in ancient Europe.

PCR primers that can detect low levels of Mycobacterium leprae DNA.

There are several specific PCR-based methods to detect Mycobacterium leprae DNA, but the amplicons are quite large. For example, primers that target the 36-kDa antigen gene and are in common diagnostic use yield a 530-bp product. This may be a disadvantage when examining samples in which the DNA is likely to be damaged and fragmented. Therefore, two sets of M. leprae-specific nested primers were designed, based on existing primer pairs which have been shown to be specific for M. leprae. Primers that targeted the 18-kDa antigen gene gave an outer product of 136 bp and inner product of 110 bp. The primers based on the RLEP repetitive sequence yielded a 129-bp outer product and 99-bp nested product. With dilutions of a standard M. leprae killed whole-cell preparation as the source of DNA, both single-stage and nested PCR were performed after optimisation of the experimental conditions. Compared with the 36-kDa antigen gene primers, the 18-kDa antigen gene outer primers were 100-fold more sensitive and the RLEP outer primers were 1000-fold more sensitive. As an illustration of two possible applications of these new primers, positive results were obtained from three skin slit samples from treated lepromatous leprosy patients and three archaeological samples from human remains showing typical leprosy palaeopathology. It was concluded that these new primers are a useful means of detecting M. leprae DNA which is damaged or present at a very low level.