In its upcoming November 14th issue, the prestigious science magazine Nature publishes, as a major article, results from a 5 year-long series of experiments conducted in the laboratory of Professor Denis Duboule, from the Dept of zoology and animal biology at the University of Geneva, Switzerland, aiming at understanding how, during embryonic development, our digits are positioned at the ends of both arms and legs. An initial response to this question is proposed, which will open doors towards a better understanding of the many malformations that affect digits at birth.

In its November 14th issue, the magazine Nature reports the results of a long-term experimental approach, carried out by Drs Marie Kmita and Yann Hérault in the laboratory of Prof. Denis Duboule, the aim of which was to understand the genetic mechanism whereby digits are correctly positioned at the end of our limbs. Indeed, about 15 years ago, the same laboratory had discovered that those architect genes, i.e. genes necessary for the proper construction of the body, were aligned along the chromosome, following the same linear order as the parts of the limbs they would construct; first the genes for the upper-arm, then genes for the fore-arm and, finally, genes for the digits. Since then, this laboratory has tried to understand the enigmatic mechanism underlying such a phenomenon.

By using a genetic technology which was developed for this purpose, Duboule's team, after a period of 5 years, could get an initial response as to the nature of the underlying mechanism; the center that 'controls' the function of genes in digits is positioned asymmetrically on one side of the series of genes. Consequently, only those genes at one extremity, closest to this control center, are functional in digits; the extremity of the genes' series corresponds to the extremity of the limbs.

This study, largely based upon in vivo chromosome engineering, was made possible by the unusual logistic possibilities that the University of Geneva is offering to this group of research, in terms of animal facilities. Mainly due to the presence of a National Pole of Excellence in Research, financed by the Swiss National Fund Agency and lead by Prof. D. Duboule. As a result, this laboratory runs one of the largest single-laboratory mouse operations, with more than 15'000 animals.

These results will help to understand how digits develop, hence they will shed light on the many digital malformations that are observed at birth in almost one of every thousand human being.

For further informations, please contact:
Professor Denis Duboule, phone 022 702 67 71
Dr Marie Kmita, phone 022 702 67 79

Geneva, November 14, 2002