title: Identification of body fluid-specific DNA methylation markers for use in forensic science.
abstract: DNA methylation, which occurs at the 5'-position of the cytosine in CpG dinucleotides, has great potential for forensic identification of body fluids, because tissue-specific patterns of DNA methylation have been demonstrated, and DNA is less prone to degradation than proteins or RNA. Previous studies have reported several body fluid-specific DNA methylation markers, but DNA methylation differences are sometimes low in saliva and vaginal secretions. Moreover, specific DNA methylation markers in four types of body fluids (blood, saliva, semen, and vaginal secretions) have not been investigated with genome-wide profiling. Here, we investigated novel DNA methylation markers for identification of body fluids for use in forensic science using the Illumina HumanMethylation 450K bead array, which contains over 450,000 CpG sites. Using methylome data from 16 samples of blood, saliva, semen, and vaginal secretions, we first selected 2986 hypermethylated or hypomethylated regions that were specific for each type of body fluid. We then selected eight CpG sites as novel, forensically relevant DNA methylation markers: cg06379435 and cg08792630 for blood, cg26107890 and cg20691722 for saliva, cg23521140 and cg17610929 for semen, and cg01774894 and cg14991487 for vaginal secretions. These eight selected markers were evaluated in 80 body fluid samples using pyrosequencing, and all showed high sensitivity and specificity for identification of the target body fluid. We suggest that these eight DNA methylation markers may be good candidates for developing an effective molecular assay for identification of body fluids in forensic science.
authors.affiliation: Medical Genomics Research Center, KRIBB, Republic of Korea; Department of Functional Genomics, University of Science of Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea.
authors.forename: Jong-Lyul
authors.initials: JL
authors.lastname: Park
authors.affiliation: Medical Genomics Research Center, KRIBB, Republic of Korea.
authors.forename: Oh-Hyung
authors.initials: OH
authors.lastname: Kwon
authors.affiliation: Medical Genomics Research Center, KRIBB, Republic of Korea; Department of Functional Genomics, University of Science of Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea.
authors.forename: Jong Hwan
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Medical Genomics Research Center, KRIBB, Republic of Korea.
authors.forename: Hyang-Sook
authors.initials: HS
authors.lastname: Yoo
authors.affiliation: DNA Forensic Division, Supreme Prosecutor's Office, 157 Banpodae-ro, Seocho-gu, Seoul, Republic of Korea.
authors.forename: Han-Chul
authors.initials: HC
authors.lastname: Lee
authors.affiliation: DNA Forensic Division, Supreme Prosecutor's Office, 157 Banpodae-ro, Seocho-gu, Seoul, Republic of Korea.
authors.forename: Kwang-Man
authors.initials: KM
authors.lastname: Woo
authors.affiliation: Medical Genomics Research Center, KRIBB, Republic of Korea; Department of Functional Genomics, University of Science of Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea.
authors.forename: Seon-Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: DNA Forensic Division, Supreme Prosecutor's Office, 157 Banpodae-ro, Seocho-gu, Seoul, Republic of Korea. Electronic address: shlee@spo.go.kr.
authors.forename: Seung-Hwan
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Medical Genomics Research Center, KRIBB, Republic of Korea; Department of Functional Genomics, University of Science of Technology, 125 Gwahak-ro, Yuseong-gu, Daejeon, Republic of Korea. Electronic address: yongsung@kribb.re.kr.
authors.forename: Yong Sung
authors.initials: YS
authors.lastname: Kim
mesh_terms: D001774:Blood Chemical Analysis; D002582:Cervix Mucus / Q000737:chemistry*; D016172:DNA Fingerprinting / Q000379:methods; D019175:DNA Methylation; D005260:Female; D005819:Genetic Markers; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D012463:Saliva / Q000737:chemistry*; D012661:Semen / Q000737:chemistry*; D017422:Sequence Analysis, DNA / Q000379:methods
chemical_list: D005819:Genetic Markers
keywords: Aging; Body fluid identification; DNA methylation; Epigenetics; Forensic