cystic

Conditions which are not currently on the medical exemption list include Parkinson's disease, cystic fibrosis and motor neurone disease.

These include Huntington's disease, cystic fibrosis and some rare inherited cancer conditions.

It is thought more than 61,000 patients in the UK need it, including those with pancreatic cancer, cystic fibrosis and chronic pancreatitis.

The most obvious way that a pair of blood-related parents might increase health risks for a child is through a recessive disorder, like cystic fibrosis or sickle cell disease.

The surgery was done in two stages - first, removing the parasitic twin, then extracting the cystic mass from surrounding organs.