The Habsburgs came seemingly from nowhere (but specifically from Austria) to take control of much of Europe and colonial stakes in the America over a period of several centuries. In addition to this vast empire, the family also became known for its distinctive facial features, including the “Habsburg jaw” and the “Habsburg lip.”
It’s long been suspected the facial condition came from inbreeding within the royal family, but new research claims to prove a link between the trademark chin and numerous unions of cousins, uncles and nieces and other dubious pairings.
“The Habsburg dynasty was one of the most influential in Europe, but became renowned for inbreeding, which was its eventual downfall. We show for the first time that there is a clear positive relationship between inbreeding and appearance of the Habsburg jaw,” lead researcher Professor Roman Vilas from Spain’s University of Santiago de Compostela explained.
A new study published in the Annals of Human Biology details how ten maxillofacial surgeons diagnosed facial deformity in 66 realistic portraits from art museums around the world of 15 members of the Habsburg dynasty. The surgeons diagnosed each member of the family with different degrees of mandibular prognathism, otherwise known as “Habsburg jaw,” as well as aspects of maxillary deficiency, which includes features like a prominent lower lip and overhanging nasal tip.
The study authors found a correlation between the two conditions, suggesting that the Habsburg jaw is really characterized by the shape of the upper lip and nose as well as the chin. More importantly, the entire look shares a common genetic basis.
The research stops short, however, of delving into the specific genetic mechanisms that might cause the facial deformity. It does suggest that Habsburg jaw should be considered a recessive condition that family members had an increased chance of developing by virtue of receiving identical forms of a gene from both parents, which is pretty much what’s been suspected all along.
Previous research has speculated that genetic disorders may have led to the ultimate extinction of the Habsburg line. Charles II of Spain, pictured above, suffered from combined pituitary hormone deficiency and distal renal tubular acidosis, which could have contributed to his impotence and infertility.
Beyond explaining the origin of the Habsburg jaw, though, Vilas is hopeful that taking a closer look at the dynasty can have broader implications.
“While our study is based on historical figures, inbreeding is still common in some geographical regions and among some religious and ethnic groups, so it’s important today to investigate the effects,” he says. “The Habsburg dynasty serves as a kind of human laboratory for researchers to do so, because the range of inbreeding is so high.”