THE gene that causes dry skin and predisposes people to eczema and asthma has been identified by scientists.

The discovery could lead to new treatments for conditions that affect millions of people, and was welcomed yesterday by a range of charities concerned with skin conditions.

According to researchers at the University of Dundee, the gene is the one whose job it is to create the protein filaggrin, which is normally found in the outermost layers of the skin. The protein is vital to ensure that the skin forms a barrier to keep water in and foreign organisms out.

All genes come in pairs, so the degree of disability depends upon whether people have a single defective copy or two. About 10 per cent of the population carry a single defective copy, and have dry and flaky skin. But those with two defective copies — about 1 in 500 people, or 120,000 in Britain — make no filaggrin and have a severe and persistent disease called ichthyosis vulgaris.

Common observation over many years has suggested a strong link between eczema, allergies and asthma. Children who have one tend to have the others, and doctors call the combination of symptoms atopic disease. Believing the likely cause to be a malfunction of the immune system, scientists in the past have looked for a common factor in immune system genes, but without complete success.

The new research, which is reported in the journal Nature Genetics, suggests that one common factor is filaggrin. Working with teams from Dublin, Glasgow, Seattle and Copenhagen, the Dundee team, led by Professor Irwin McLean, found several strong links:

The findings suggest that the weakness in the skin barrier allows allergens access, triggering the immune system changes that then lead to diseases such as asthma. The filaggrin gene is unlikely to be the sole cause of the condition but its discovery suggests new ways of treating the root cause rather than its symptoms.

SKIN DEEP

Eczema is a skin irritation characterised by itchy, red, flaky skin

It affects about five million people in Britain

There are several causes, but the most common are related to allergies

Sufferers are told to stay away from detergents, soaps and bubble baths

Millions of pounds are spent on treatments every year

Conventional remedies include antihistamines and steroid creams

Alternative treatments include evening primrose oil, tea tree oil, burdock and oatmeal

Famous sufferers have included the artist Paul Gauguin and the actors Ricky Tomlinson and Claire Sweeney

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