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A family trait made tragic by inbreeding
The Habsburgs were known for their tendency to make advantageous marriages to secure alliances. When they split their realms between two family branches, they often intermarried between these two branches to keep the family’s power strong. Unfortunately, the many marriages between relatives led to inbreeding, to such an extent that the Habsburgs lost the throne of Spain due to the genetic dead end of King Charles II. Charles suffered from a family trait, the Habsburg jaw, that was found in many of his ancestors and family members. In poor Charles’ case, the jaw became so deformed that he was unable to eat solid foods or speak easily.
The Habsburg jaw was proposed by some earlier historians to be introduced into the family by Cymburgis of Masovia, a Polish princess of the Piast family, who married Ernest the Iron and was the ancestress of all later Hapsburgs. However, portraits and statues don’t depict Cymburgis with a jutting jaw. Indeed, earlier Hapsburgs, including her husband’s great grandfather, Albert I of Germany, posses the jaw in their portraits, so why this trait was mistakenly attributed to poor Cymburgis is unknown.
The Habsburg jaw is more appropriately known as mandibular prognathism, and it is not a trait unique to the Hapsburgs. It is commonly known as an underbite and can be corrected with orthodontics in less extreme cases and surgery in more extreme forms. However, the Habsburg’s penchant for inbreeding made a rather normal trait become grotesque.
Maxillofacial surgeons studied the portraits of the Habsburgs and found that the more inbred members of the family tended to have the most deformed jaws. Surprisingly, Charles II, who was the most inbred member of the family, was not judged to have the most deformed jaw. That (dis)honor was taken by his father, Philip IV. Other members who were found to have prominent examples of the jaw in their paintings were Maximilian I, Charles V and Margaret of Austria.
The jaw, in less severe forms, was evident in family members, even when the interbreeding became less prolific. Marie Antoinette had a protruding…
