SYDNEY - Scientists at the University of Queensland's biochemistry department are set to develop a special mouse they believe will play a vital part in the investigation of human skin diseases.

Led by Joe Rothnagel, who is also a Wellcome Trust senior research fellow, the scientists intend to develop a mouse in which a key gene involved in the production of filaggrin - a multifunctional protein found in the outer layers of skin - will be missing.

Filaggrin is suspected of being human skin's natural moisturizer, and its absence is believed to cause problems such as the common scaly skin disease ichthyosis vulgaris.

Rothnagel said the human equivalent of the recently identified mouse gene was isolated in early 1996, but filaggrin could not be properly investigated without an animal model.

Now that his team has isolated the large mouse gene - 16,000 base pairs, not counting some of the regulatory segments - it can engineer the proper knockout mouse model and start investigating filaggrin. Barring unforeseen technical difficulties, Rothnagel expects to have the mouse ready by Christmas. - Mark Lawson