Absolutely, the Bowes-Lyon family has a number of members with known issues.

[Nerissa and Katherine Bowes-Lyon] (http://en.wikipedia.org/wiki/John_Bowes-Lyon#Nerissa_and_Katherine_Bowes-Lyon), first cousins to the Queen, were committed to asylums and then abandoned by the Royals, with Nerissa dying in obscurity, buried in a paupers grave. Only outcry from the public following a TV documentary and newspaper stories forced the Windsors to pay for a decent gravestone.

A number of other family members were incarcerated in the same hospital.

Katherine Bowes-Lyon died in March of this year, I am unable to find out if the funeral was attended or a gravestone paid for by any of the Windsors.

Neither George IIIs madness or the Bowes-Lyon issues are clearly known genetic disorders (although the latter certainly manifested somewhat like one). In Georges case it was apparently a one-off, so it wasnt perceived as a 'family issue' as such and therefore doesnt really fit your question. His madness caused many issues at the time and helped parliament in its gradual creep for replacing monarchal power with its own. The Bowes-Lyon family were somewhat obscure (compared to the royal line) and thus once the ladies were sequestered away with their illness they were out of the public eye.

The only true recent genetic disorder is of course Queen Victorias hemophiliac gene that she passed on to some of her children. At the time there was no true understanding of mendellian genetics and so no definitive inheritable link was made. People knew that Leopold was ill, he was diagnosed as a child, but this doesnt seem to have been an issue at the time.

Being a fourth male he wasnt expected to inherit the crown, he was unable to have a military career because of his illness, but never the less conducted a fairly normal life.

Hemophilia is a largely hidden illness and because genetic transmission wasnt really understood there was little stigma to the condition. Thus there seems, from what I can see, to have been little real 'PR' repurcussions to it. People knew that it was 'sort of' transmissible, but they didnt really understand the whole dominant/recessive thing either. I believe he had a few issues finding a wife, primarily because he was a bit 'sickly' rather than because he was carrying a genetic defect that was transferrable to his kids.

Note: By the 1800s the heritability aspect of Hemophilia was starting to be understood (mostly only males, women probably just carriers). However unlike more modern times evidence of scientific discoveries often took time to gain 'weight' in the public conscience. For example Mendel 'discovered' modern genetics (and the rules covering Hemophelia) but was only himself discovered after his death. So being a Hempholiac male today would make people FAR FAR more aware of the dangers of having children with someone with the disease or a carrier. As such Leopolds illness wasnt a PR exercise that had to be handled.

The reference to the Bowes-Lyon family is incorrect, because Nerissa and Katherine Bowes-Lyon were not of Royal lineage. Remember there was a minor outcry at the Queen Mother at the time she married Prince Albert(the later King George) because she was a 'commoner'

A better example is Prince John. There are a lot of stories that they locked him away, and while its true he was rarely seen in public, the modern view is that he had a good life, and was well looked after