What causes ADPKD?
ADPKD is caused by a genetic fault that disrupts the normal development of some of the cells in the kidneys and causes cysts to grow.
Faults in one of two different genes are known to cause ADPKD. The affected genes are:
- PKD1 – which accounts for 85% of cases
- PKD2 – which accounts for 15% of cases
Both types of ADPKD have the same symptoms, but they tend to be more severe in PKD1.
A child has a one in two (50%) chance of developing ADPKD if one of their parents has the faulty PKD1 or PKD2 gene.
Autosomal recessive polycystic kidney disease (ARPKD) is a rarer type of kidney disease which can only be inherited if both parents carry the faulty gene and in this type problems usually start much earlier, during childhood.
Non-inherited ADPKD
In around one in four (25%) cases, a person develops ADPKD without having a known family history of the condition.
This could be because the condition was never diagnosed in a relative, or a relative with the condition may have died before their symptoms were recognised.
In around one in 10 cases of ADPKD, the mutation develops for the first time in the affected person. It's not known what causes this to happen.
The affected person can pass the faulty gene on to their children in the same way as someone who's inherited it from a parent (see above).