Habsburg chin, Habsburg's chin, Habsburg jaw or Habsburg's jaw.
Carlos II of Spain, ‘The Bewitched’: cursed by aspartylglucosaminuria?
Carlos II of Spain (1661–1700), last of the Spanish Habsburg dynasty, was known as El Hechizado (The Bewitched) because of his poor health and feeble nature. He suffered from a range of disorders including developmental delay, intellectual disability, dysarthria, skeletal deformity, recurrent infections, epilepsy and infertility. The Spanish branch of the Habsburg royal family was characterised by marked inbreeding, and the male line died out with Carlos II. Various diagnoses have been proffered to explain Carlos II’s infirmity, though none fully explain the breadth of his ailments. As illustrated here, it may be that aspartylglucosaminuria, an autosomal recessively inherited lysosomal storage disorder, can account for the characteristic facial appearance of the Habsburgs, and for the wide variety of other features exhibited by Carlos II.
Aspartylglucosaminuria
Aspartylglucosaminuria is an autosomal recessively inherited lysosomal disorder of in which glycoasparagines, mostly aspartylglucosamine, are deposited and build up in several different tissues, including the nervous system. Most cases have been described in Finland, where a high carrier rate is prevalent, although mutations are found worldwide.1 2 Being autosomal recessively inherited, the prevalence is increased in populations with a high degree of consanguinity.
Characteristic clinical features typically include normal birth and early infancy followed, at the age of 2–3, by delayed speech and motor development with intellectual disability.3 A weak suck in infancy has also been described.4 A distinctive facial appearance is present, consisting of widely spaced eyes (hypertelorism), puffy eyelids, small ears, full lips, a square and prominent jaw, a cupid bow shape of the upper lip and a short, broad nose. Patients have frequently been described as appearing prematurely aged.5 In addition, there is frequently relative macrocephaly earlier in development, which may evolve into relative microcephaly, presumably due to retardation of skull growth as the disease progresses6
Not infrequently, skin lesions are present. A wide variety of such lesions have been described, including erythema, herpetic-appearing lesions, facial angiofibromas, seborrhoea, gingival overgrowth, buccal oedema and occasionally tumours.7 8 Fistulas have also been described.9 Bony abnormalities are often seen, including thick and misshapen ribs, scoliosis and thickened calvaria.3 Other suggestive features include recurrent pulmonary infections, diarrhoea, hypermobility of connective tissues, hernias, movement disorders and epilepsy.2Intellectual disability is typically mild early on, though verbal dysfunction is most prominent, with later progression to severe levels by late adulthood.4 A range of psychiatric symptoms may be present.
The course is progressive. Most patients die in the fifth decade. Somewhat interestingly, as was the case in Carlos II, patients generally become very apathetic/abulic before death.2
Carlos II, The Bewitched
Carlos II was a sick and frail monarch, and the tragic end product of years of disastrous inbreeding. Ascending the throne at the age 4, he ruled over the Spanish Empire ineffectually for 35 years. His death in 1700 without an heir threw Europe into the convulsive and disastrous War of the Spanish Succession. Its end result was to weaken both Spain and France, allowing the rise of the English.10
Carlos II exhibited many features described in aspartylglucosaminuria. Contemporary sources record that he was ‘big-headed’ and a ‘weak breast-fed baby’. The bones of his cranium had not fused at the age of three, and he was unable to walk until well after the age of 6.11 Carlos II was unable to speak until the age of four, and thereafter acquired little language.11 12 He also had prominent dysarthria, with his tongue being described as ‘trabado [locked], with such a fumbling in his speech’.11 In addition, he was described as showing little interest in his surroundings. He had severe intellectual disability, and was most commonly described as ‘mentally retarded’.13He had prominent psychiatric disturbance, and was melancholic, and excessively superstitious.13
He also suffered from chronic and episodic diarrhoea. Late in life, he developed seizures.12 He had frequent pulmonary infections from a young age, and at autopsy his lungs were said to be ‘corroded’.13 He was also described as being generally ‘swollen’, suggestive of oedema.12 Somewhat interesting, too, is the description of cutaneous lesions, with mentions of a ‘herpetic rash on both cheeks’, and a discharging wound that ‘oozes underneath the right ear’, which may represent an abscess or fistula.11 Of later monumental historical significance is his well-known sterility.11The autopsy is also reported to have demonstrated a heart the size of a peppercorn, intestines rotten and gangrenous, a single testicle ‘black as coal’ and ‘a head full of water’.12
Most characteristic, however, is the distinctive facial appearance, well documented in multiple portraits. There is the strong, square jaw (the famous ‘Habsburg jaw’), a large tongue, plump, round lips, a cupid bow upper lip, a flat, broad nose and large forehead, all reminiscent of the typical findings of aspartylglucosaminuria (figures 1 and 2). He is also frequently described to have severe difficulty eating, with near continuous drooling.
