Evolution of the amelogenin Paris, France gene in toothed and toothless vertebrates

Amelogenin proteins constitute the major organic contents in forming enamel, but some previously published data indicate that the amelogenin gene could be present in several species lacking teeth or functional enamel. Therefore, amelogenin could have another, still unknown, function other than contributing to enamel formation. In order to test this hypothesis, the presence of this gene has been searched for in various vertebrates. We first compared the mammalian amelogenin sequences available in the literature to obtain the best chance of a successful detection of this gene in phylogenetically distant species. Marc Girondot, Université Paris 7, Unité de Using this analysis, we have shown that the occurrence of the amelogenin gene Recherche Associèe: Evolution et Adaptations des Systèmes in the Y chromosome of primates and of an artiodactyl species is probably due Ostèomusculaires (Case 7077), 2 place to two independent duplications from genes on the X chromosome. Primers for Jussieu, 75251 Paris cedex 05, France PCR have therefore been synthesized and tested in eight species, five possessing Telefax: +33-144275653 teeth (human, two phylogenetically distant lizards, and two phylogenetically E-mail: [email protected] distant actinopterygians) and three lacking teeth (chicken and two