The discrimination of three genotypes in STR locus D5S818 based on ultraviolet spectroscopy-chemical pattern recognition

Abstract

A simple, sensitive and low-cost approach for genotyping of a short tandem repeat (STR) based on ultraviolet spectroscopy (UVS)-chemical pattern recognition is presented. Genotypes 10-11, 11-11 and 11-12 of STR locus D5S818 are selected as the objective subjects. Through optimized polymerase chain reaction and ultraviolet spectrum measurement, ultraviolet spectra of all samples are obtained. Based on principal discriminant variate (PDV) and discriminant partial least squares (DPLS), PDV and DPLS models are established by using ultraviolet spectra as recognition variables. By optimizing the weight parameter λ in PDV algorithms and the number of latent variables in DPLS algorithms, optimal PDV and DPLS models are obtained. The two optimal models have good separability and robustness, as well as excellent prediction accuracy, which provides a methodological support for establishing ultraviolet spectrum-based classification for all genotypes of D5S818 locus and other STR loci.