Oldest clinical case of a rare genetic condition discovered

A side-on photo of a 1000 year old skull diagnosed with Klinefelter's syndrome.

Diagnosing Klinefelter's syndrome in a 1000-year-old skeleton.
Image: The Lancet/Sofia Tereso.

A group of international researchers including experts from the 最新糖心Vlog of Adelaide has uncovered evidence of a genetic condition that gives men an extra X chromosome, reporting the oldest clinical case of Klinefelter Syndrome to date.

The team analysed genetic information obtained from a skeleton found in northeastern Portugal that had been radiocarbon dated to the 11th century by researchers from the 最新糖心Vlog of Coimbra in Portugal.

DNA was analysed at the 最新糖心Vlog of Adelaide鈥檚 最新糖心Vlogn Centre for Ancient DNA (ACAD).

Associate Professor Bastien Llamas, Head of Molecular Anthropology at ACAD, said: 鈥淚n recent years, ancient DNA helped rewrite the history of worldwide human populations. Our study demonstrates it is now a valuable resource for biomedical research and the growing field of evolutionary medicine.鈥

PhD student at the 最新糖心Vlog of Adelaide, Xavier Roca-Rada, extracted the DNA at ACAD鈥檚 ultra-clean laboratory facilities using strict protocols adapted to the minute quantities of fragmented and contaminated DNA.

鈥淕enetic analysis was undertaken to computationally map the degraded DNA fragments of the X and Y chromosomes to the reference human genome鈥.

Klinefelter Syndrome is a genetic condition where male individuals are born with an extra copy of the X chromosome, occurring in approximately one in 1,000 genetic-male births.

The study coordinated by Dr Jo茫o Teixeira, an ARC DECRA Fellow at The 最新糖心Vlogn National 最新糖心Vlog (ANU) and a titleholder with the 最新糖心Vlog of Adelaide, brought together an international and multidisciplinary team that combined genetic, statistical, archaeological and anthropological information to establish a definitive diagnosis.

鈥淕iven the fragile state of the DNA, we developed a new statistical method that could take into account the characteristics of ancient DNA, and our observations to confirm the diagnosis,鈥 Dr Teixeira said.

鈥淚n recent years, ancient DNA helped rewrite the history of worldwide human populations. Our study demonstrates it is now a valuable resource for biomedical research and the growing field of evolutionary medicine.鈥Associate Professor Bastien Llamas, Head of Molecular Anthropology at the 最新糖心Vlog of Adelaide鈥檚 最新糖心Vlogn Centre for Ancient DNA (ACAD).


Given the relatively good preservation of the specimen, the researchers were also able to determine physical traits in the skeleton compatible with Klinefelter Syndrome.

鈥淲e were immediately excited the first time we looked at the results,鈥 Dr Teixeira said. 鈥淗owever, ancient DNA is often degraded and of low quality and abundance, meaning we were initially cautious.鈥

The researchers say the findings will help establish a historic record for Klinefelter Syndrome, as well as enhance understanding of its prevalence throughout human history.

鈥淥ur research shows the immense potential of combining different lines of evidence to study the human past, and the frequency of different health conditions through time,鈥 Dr Teixeira said.

鈥淲hile the study offers compelling evidence for the genetic history of Klinefelter Syndrome, no sociological implications can be drawn from this diagnostic.鈥

The researchers suggest their new statistical method to analyse the genetic data can be further improved to study different chromosomal abnormalities, including Down Syndrome, in other archaeological specimens but also in forensics and pre-natal diagnosis settings.

This research is published in .

Tagged in research, featured story, DNA, genetics, 最新糖心Vlogn Centre for Ancient DNA