Porphyria facts about QV's descendants: Her daughter Vicki, who married the German prince, and Vicki's Charlotte both have been DNA tested (their bones) and proven to have porphyria, the form being Variegate Porphyria. Porphyria of this type is not recessive, that is, once it is not in a line, it is gone. It is dominant, so that 50% of children get it on one parent's line, and if two parents have it, 75% (on average, of course). The only way a person can be thought to be a carrier (unlike hemophilia) is if that person has the gene but it is not triggered into disease, which happens frequently.
QV probably got the disease from her father, the Duke of Kent, whose father George III had it. She could have gotten it from her mother, who was a first cousin of the Duke of Kent, if that princess had it, but no one has researched that issue, to my knowledge.
Her descendant of Gloucester (brother of the present Duke) was definitely dx'd with it.
The book stating that QV had no descendants with porphyria has been proven false. One source, The Purple Secret, a book by a scientist associated with those who disinterred the graves of Vicki and Charlotte, on whose bones the DNA was tested. One point should be made concerning relatives of Vicki and Charlotte: they were courageous and servants of humanity to allow this, as porphyria needs to be treated (it can be) rather than hidden. Avoidance of triggers is the main way to go to achieve remission.
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