Differentiating between monozygotic twins through next-generation mitochondrial genome sequencing.
Monozygotic (MZ) twins, considered to be genetically identical, cannot be distinguished from one another by standard forensic DNA testing. A recent study employed whole genome sequencing to identify extremely rare mutations and reported that mutation analysis could be used to differentiate between MZ twins. Compared with nuclear DNA, mitochondrial DNA (mtDNA) has higher mutation rates; therefore, minor differences theoretically exist in MZ twins' mitochondrial genome (mtGenome). However, conventional Sanger-type sequencing (STS) is neither amenable to, nor feasible for, the detection of low-level sequence variants. The recent introduction of massively parallel sequencing (MPS) has the capability to sequence many targeted regions of multiple samples simultaneously with desirable depth of coverage. Thus, the aim of this study was to assess whether full mtGenome sequencing analysis can be used to differentiate between MZ twins. Ten sets of MZ twins provided blood samples that underwent extraction, quantification, mtDNA enrichment, library preparation, and ultra-deep sequencing. Point heteroplasmies were observed in eight sets of MZ twins, and a single nucleotide variant (nt15301) was detected in five sets of MZ twins. Thus, this study demonstrates that ultra-deep mtGenome sequencing could be used to differentiate between MZ twins.
Shanghai Key Laboratory of Forensic Medicine, Institute of Forensic Science, Ministry of Justice, P. R. China, Shanghai 200063, China; State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, China.
Zheng
Z
Wang
Shanghai Key Laboratory of Forensic Medicine, Institute of Forensic Science, Ministry of Justice, P. R. China, Shanghai 200063, China.
Ruxin
R
Zhu
Shanghai Key Laboratory of Forensic Medicine, Institute of Forensic Science, Ministry of Justice, P. R. China, Shanghai 200063, China; State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, China.
Suhua
S
Zhang
Shanghai Key Laboratory of Forensic Medicine, Institute of Forensic Science, Ministry of Justice, P. R. China, Shanghai 200063, China.
Yinnan
Y
Bian
State Key Laboratory of Genetic Engineering, Institute of Genetics, School of Life Science, Fudan University, Shanghai 200433, China.
Daru
D
Lu
Shanghai Key Laboratory of Forensic Medicine, Institute of Forensic Science, Ministry of Justice, P. R. China, Shanghai 200063, China. Electronic address: lichengtaohla@163.com.
Chengtao
C
Li
D000328:Adult; D002681:China; D004272:DNA, Mitochondrial / Q000097:blood / Q000737:chemistry*; D053803:Forensic Genetics / Q000379:methods*; D054629:Genome, Mitochondrial; D015698:Genomic Library; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008875:Middle Aged; D059645:Mutation Rate; D017354:Point Mutation; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA; D014430:Twins, Monozygotic
D004272:DNA, Mitochondrial
Forensic genetics; Massively parallel sequencing (MPS; Mitochondrial genome (mtGenome); Monozygotic twins