Anomalous Gender Assignation by the Amelogenin Sex Gene

By: Ashraf Aboaleid , Othman Elansari , Mohamed Algriw

Technical department for identification of missing persons Lab, Ministry of Martyrs and Missing Persons, Tripoli - Libya.

Issue: Vol 21 |First Issue | 2015

article language: English

Abstract:

Accurate human gender identification relies on a specific locus (gene) on DNA known as Amelogenin, which has crucial applications in many scientific disciplines, such as prenatal diagnosis of genetic disorders related to this gene. Molecular genetics techniques are specifically used to detect length variations in the X and Y homologues of this gene for gender determination. This sex test is an integral part of PCR multiplex kits used for DNA profiling. However, a number of results have shown an anomaly (ambiguity) where the male Y chromosome is absent in some males, resulting in a genotype showing only the female X chromosome, even though males typically have both X and Y chromosomes at this locus. This study aims to determine the frequency of this anomaly, called AMELY null (Y chromosome dropout), in the Libyan population. This study revealed the presence of a mutation at the Amelogenin sex-determining locus at a frequency of 0.1175% in the Libyan population, manifested as the loss of the Y chromosome in males. These results show that gender determination using this technique should be interpreted cautiously, especially in forensic cases where the sample obtained from the crime scene is of unknown gender.