Irish scientists have discovered that two skeletons in a medieval Gaelic cemetery show signs of an extremely rare condition caused by two different genetic mutations, one of which was previously unknown.

Two cases of multiple osteochondromas

The thousand-year-old Ballyhanna Cemetery was discovered in 2003 during the construction of a major ring road in County Donegal, Northern Ireland, containing the remains of approximately 1,300 individuals. In the context of the work published inEuropean Journal of Human GeneticsA team of researchers from the University of Belfast and Trinity College Dublin discovered that two men buried there were affected by benign bone tumors known as multiple osteochondromas.

This extremely rare condition, caused by a mutation within the EXT1 gene, is estimated to affect approximately one in 50,000 people, and during the same period, a careful analysis of their Skeletons It is revealed that they are not related and that their deaths are centuries apart.

Even more disturbingly, it changed Genetic mutations The cause of their illness was different. Although the first was already observed in modern patients, the second was completely unknown to science. According to the team, this is the first evidence of a new pathological mutation within old genomic data.

Common signs of bone stress and poor health

Despite their benign nature, these bony tumors are known to cause limb deformity and nerve compression, causing severe pain that may leave both individuals severely disabled.

Examination of other skeletons in the cemetery, believed to have been the burials of farmers, laborers, merchants, artisans, priests, and very poor people, revealed signs of normal skeletal stress and poor health.

” Detecting mutations that cause serious diseases through whole genome sequencing has been a major medical advance in recent years, but this is the first time it has been applied to ancient individuals. “, underlines Dan Bradley, co-author of the study. ” This work demonstrates the important contribution that ancient DNA analysis can make to understanding conditions that still affect us today. »