Studies of British and Swedish families with the condition revealed a genetic change in a key chemical that controls water loss from the body.
This disease is found amongst one in 40,000 people, its is seen in these people that the skin is thickened on the palms and soles.
Researchers in London say the discovery will aid understanding of how the skin moisturises itself.
David Kelsell, professor of human molecular genetics at Queen Mary, University of London, who led the team said that, “The genetic study gives an insight into how the skin barrier functions”.
He said that the research, published in The American Journal of Human Genetics, could also help investigations into other skin conditions.
Prof Kelsell told BBC News that,”This may help us understand more about how the skin moisturises itself naturally.”
“Everyone knows that when you sit in the bath for an hour your skin goes white and wrinkly. This is what happens in people [with the skin condition]- but it just happens a bit quicker.”
The condition is called diffuse non-epidermolytic palmoplantar keratoderma.
The underlying cause is a fault in a substance called aquaporin 5, which plays a role in the generation of saliva, tears and other secretions.
The research shows it is also present in the skin, with higher amounts in the hands and feet.
The gene change appears to make the skin more porous, allowing water to permeate the skin more rapidly.