This paper discusses verification of eye and skin color predictors in various populations.
In this study, researchers validated eye and skin color predictors using new sample sets and confirmed that they can be applied in various populations, including African-American, South Asian (dark), East Asian (light), European, and mixed populations. The outputs were either predictive or inconclusive. Predictions were then compared against the actual eye and skin colors of the tested individuals. Error rates were low for the predictors that describe the eye and skin color exclusively (non-brown or non-blue and non-white or non-dark, respectively). The rates were higher for the predictor that describes individual eye colors (blue, brown, and intermediate/green) because of uncertainties with the green eye color prediction. This investigation deepens the insight into these predictors and adds new information. Recently, three phenotypic predictors, two for eye colors and one for skin color, have been published. These predictors are well defined by a selection of single nucleotide polymorphisms (SNPs) and unambiguous instructions on how to interpret the genotypes. These standardized approaches are advantageous because they can be applied in diverse laboratories, leading to the same outcome and offering the opportunity for validation. For these tests to be used on the characterization of human remains, they should be validated on various populations to perform reliably without prior knowledge of ethnic origin. Validation of testing methods is an essential feature in all scientific endeavors, but it is particularly important in forensics. Due to the sensitive nature of these investigations and the limited sample size, it is crucial to validate all employed procedures. This includes novel forensic phenotypic DNA tests to learn more of their capabilities and limitations before incorporating them as routine methods. Ideally, validations are performed on large sample sets that mimic real cases. (Published Abstract Provided)