Methylation-Based Age Estimation Model Construction And Its Effectiveness Evaluation

Objective:This study aims to find the age-related DNA methylation loci in northern Chinese Han male population and build age prediction model.Methods:Twenty-one candidate methylation loci were screened based on bibliographic searches and previous studies.21 DNA fragments were downloaded from UCSC genome browser.Primer design with Agena Bioscience EpiDesigner software,had a total of 153CpG loci.Finally,The DNA methylation levels of 476 blood samples from Chinese Han males were detected for 21 amplicons using EpiTYPER technology platform,and data on153 DNA methylation loci were obtained.All the methylation data results were analyzed by Pearson correlation coefficient,correlation coefficient|r|>0.5,AIC value,and significance P value(P<0.005).Fitting linear regression equation to construct age prediction model.Results:After correlation analysis,8 age-related DNA methylation loci were finally screened from 153 CpG loci.CpG1,CpG2,CpG4,CpG7,CpG8 were located on TRIM59,RASSF5,Clorf132,CSNK1D,ELOVL2,CpG5,CpG6 on PDE4C,and CpG3 on chr17:21452808.Based on the 8 loci,352 samples were used for model construction.A multivariate linear regression age estimation model was constructed(R~2=0.93),with mean absolute deviation(MAD)of 2.69 years old.When 109 samples were used for model validation,the MAD was 3.80 years old.The test was repeated 3 times in 15 new samples,with MADs of 4.08,4.68 and 3.93 years old,respectively,and 15 bloodstain samples with MAD of 3.99 years old.Conclusion:This model built in our study can be used for age estimation in northern Han Chinese males and can be used in the crime investigation to narrow down the suspects.