A pilot study of the ERCC1 and XPF genes in forensic age estimation / 中国法医学杂志

ABSTRACT

Objective The aim of this study is to detect the mRNA and protein expression levels of ERCC1 and XPF genes among different age groups of healthy Chinese Han individuals,and to analyze the correlation between the mRNA and protein expression levels andthe age of individuals in order to find new molecular markers for forensic age estimation.Methods Peripheral blood samples were obtained from 150 unrelated healthy Chinese Han individuals.The plasma was centrifuged from the whole blood by gradient centrifugation,and the totalRNA was extractedwithTrizol fromperipheral blood mononuclear cells(PBMCs).Real-time quantitative reverse transcription polymerase chain reaction (RT-qPCR) was used to quantitatively analyze the mRNA relative expression levels of ERCC1and XPF in PBMCs.Enzyme linked immunosorbent assay (ELISA) was used to quantitatively analyze the protein expression levels of ERCC1and XPF in plasma.Results There were no significant differences in the mRNA relative expression levels of ERCC1 and XPF in PBMCs between males and females(P＞0.05).Significant differences were found in the mRNA relative expression levels of ERCC1 and XPF between different age groups (P＜0.05).Regression analysis showed thatthe mRNA relative expression levels of ERCC1 and XPF were both negatively correlated with age.The correlation coefficients(r) were-0.578 and-0.844,respectively.When the age was used as independent variable(x) and the mRNA expression relative level as dependent variable (y),the fitting curveswere Y=3.3E-5X2-0.0261X+1.9175 (R2=0.3244,P＜0.01),Y=0.0003X2-0.0459X+2.0439 R2=0.729,P＜0.01),respectively.There were no significant differences inthe protein expression levels of ERCC1 and XPF in plasma between different age groups or genders (P＞0.05).Conclusion The mRNA relative expression levels of ERCC1 and XPF in PBMCsdeclined with the increase of age,however,the protein expression levels in plasma were unrelated to age.ERCC 1 and XPF genes can be used asnew molecular markers for forensic age estimation,so as to providetheoretical basis for establishing the mathematical model of ERCC1/XPF genesin concern ofindividual ages.