A 1000-year-old case of Klinefelter's syndrome diagnosed by integrating morphology, osteology, and genetics

The skeleton of a human being buried over 1000 years ago, in the medieval archaeological site of Torre Velha, in north-eastern Portugal, was referred to us for analysis and investigation (appendix). Furthermore, using a novel Bayesian method, allowing us to probabilistically assign individuals to karyotypes based on the number of sequencing reads—or DNA fragments sequenced—mapping to the X, Y, or autosomal chromosomes, we concluded our individual's karyotype to be 47,XXY, and rejected models of contamination of XXY and XX or XY (figure; appendix). To overcome these limitations, we have devised a novel Bayesian method, which, we believe, is a potentially efficient statistical way of analysing fragmented DNA from a variety of sources (eg, ancient DNA, cell-free DNA, and DNA from forensic cases).