Screening and validation of age-related DNA methylation microhaplotypes in mouse blood
Objective The DNA methylation microhaplotype(DMH)refers to the combination of multiple methylation sites within a very short range,and these haplotypes show wide diversity.We carried out screening and validation of age-related DMHs in mouse blood.Methods We initially constructed a theoretical dataset of DMHs based on the mouse reference genome.We then screened age-related DMHs by Spearman's rank correlation analysis,using high-throughput sequencing information for DNA methylation in mouse blood from a network database.Finally,cross-validation was performed using a validation dataset.Results A total of 6787 142 DMH sites were identified within 50 bp in the mouse genome,including 98.64%of single-digit CpG sites.A total of 5835 age-associated DMHs were screened in 58 mouse blood samples(|rho|>0.5,P<0.01),accounting for 0.086%of DMHs.Finally,we validated the top 100 age-associated DMHs with high correlation in 95 independent samples,Resultsing in 44 loci.Conclusions The age-associated DMHs screened in this study may be useful in future studies of apparent age prediction using mouse blood and in aging studies.