Sex molecular diagnosis on critical samples: Comparison of different methodologies

Abstract

A fundamental question of the personal identification is the sex determination. Sometimes, the anthropological sex diagnosis is not trustworthy; especially when facing up to sub-adult skeletal remains or very degraded samples. Because of that, the molecular analysis could constitute a fundamental tool to establish a reliable sex diagnosis. Nevertheless, when analysing critical samples, the molecular sex diagnosis could show some difficulties when dealing with Low Template DNA (LTD) and stochastic phenomena.Through this study 4 different methodologies were compared for the molecular sex diagnosis on critical samples (LTD samples). Concretely, 60 samples were analysed from ancient human skeletal remains of different antiquity (Chalcolithic and Bronze Age). The sex diagnose was determined by 2 different autosomal STR commercial kits (AmpFℓSTR® MiniFiler™ PCR Amplification Kit, and AmpFLSTR® NGM™ PCR Amplification Kit), which includes an amelogenine gen marker; The other methodology contemplated the amelogenin gen amplification also, performed by real time PCR (RTPCR). The last technique was based on the Insertion-Deletion Polymorphisms of the X-chromosome analysis (X-INDELs). Through these analyses, we compare the 4 different methods, evaluating advantages and disadvantages and comparing also with the anthropological sex diagnosis.