Скачать или смотреть Use of the IRISPLEX System Markers for Eye Color Prediction in an Admixed Brazilian Population

The inference of externally visible characteristics (i.e. skin, eye and hair
color, height and facial features) from biological trace samples is known as
Forensic DNA Phenotyping. The IrisPlex system is a forensically validated tool for eye color prediction from DNA. The IrisPlex system has been reported to reach predictive power, but validations have mainly been carried out in homogeneous populations with minor admixture. In this study, we present an evaluation of the IrisPlex system in an admixed population of 611 Brazilian individuals. Genotypes were obtained for all IrisPlex markers, distributed in 06 genes / gene regions (SLC45A2, IRF4, TYR, OCA2, HERC2 and LOC105370627). The predictions were carried out using the IrisPlex prediction model (https://hirisplex.erasmusmc.nl/). Results were compared to the phenotypes for each individual (blue, brown or intermediate eye color), and the Area Under the Curve (AUC) and accuracy for each phenotype group were calculated using R statistics software (packages MASS, mlogit, ROCR,
reportROC and caret). AUC values were found to be 0.878 for blue eye, 0.664
for brown eye and 0.500 for intermediate eye color. As expected for the system, intermediate phenotypes reached lower values and could not be predicted correctly for any of the individuals. In fact, when these individuals (intermediate eye color) are removed from the sample, overall prediction accuracy increases from 74.61% to 95.76%. Our results demonstrate that the IrisPlex system markers have great potential for use in admixed populations, including the Brazilian, but our results also demonstrate that the intermediate color groups are difficult to predict.