MOST people have heard of the skin complaint, psoriasis.

But it's not as widely known that people who suffer from psoriasis also have an increased risk of developing a form of inflammatory arthritis which affects both the skin and the joints. This condition -- famously suffered by the late playwright Dennis Potter -- is known as psoriatic arthritis.

We know that there is a genetic link between the skin condition and the arthritis, but to date studies have been limited to small numbers, and have not explored the new genes we now know are relevant.

So we plan to study patients with psoriatic arthritis to attempt to discover how their genetic make-up differs, not only from the general public but also from patients with psoriasis alone and arthritis alone.

By doing this we hope to solve the conundrum of this "disease within a disease". A better understanding of the genetic factors behind the condition will help us to develop new treatments and may even, in future, help us prevent this problem developing.

Our team at the Arthritis Research Campaign Epidemiology Unit at the University of Manchester plan to recruit 400 people who currently have both psoriasis and some kind of inflammatory arthritis.

A research nurse will visit volunteers at your home or at your next clinical appointment in your local hospital, where a basic medical history will be taken, an examination performed and a single blood sample taken. If you can help please contact me for an information pack.

Peter Bradburn,

ARC Epidemiology Unit,

University of Manchester.

0161 275 5037

peter.bradburn@fs1.ser.man.ac.uk