El diagnóstico genético del sexo mediante el test de la amelogenina: Métodos y posibles fuentes de error

Abstract

Sex typing of biological evidences is crucial in forensics in general, and in criminal investigation, in particular. The amelogenin - a protein codified in the sexual chromosomes - has been used with these purposes since the last decade of the past century. There are sequence and size divergences between the X and Y-codified alleles of this gene (AMELX and AMELY). This fact is in the base of its using as a genetic sex typing test. However some cases in which the amelogenin test outcome does not correspond with the legal (official) sex have been published. The present work offers a revision of the published protocols of the amelogenin sex typing test, locating the most common amplified areas of this gene, and the different techniques employed to detect the AMELX and AMELY fragments. Finally, the conditions in which the amelogenin test can differ from the phenotypic sex are analyzed. These conditions must be taken into account in order to avoid potentially serious errors in the forensic investigation.