DNA identification of monozygotic twins

Area of Science:

• Genetics
• Forensic Science

Background:

• Monozygotic (MZ) twins share identical DNA, making differentiation challenging.
• Short tandem repeat (STR) analysis is standard but insufficient for distinguishing MZ twins.

Purpose of the Study:

• To detail a method for differentiating monozygotic twins using single nucleotide variations.
• To assess the feasibility of this method in forensic DNA analysis.

Main Methods:

• Whole Genome Sequencing (WGS) was performed on DNA from blood, buccal swabs, and saliva of three MZ twin pairs.
• Fastq data were analyzed using specialized software to detect single base differences.
• Sanger sequencing confirmed identified single nucleotide variations.

Main Results:

• No differences were found using standard STR and Y-STR profiling.
• WGS data revealed 1, 5, and 9 single base differences between MZ twin pairs.
• Variations in detected mutations were observed across different body fluid samples.

Conclusions:

• Whole Genome Sequencing can identify single base differences to distinguish monozygotic twins.
• The described WGS-based method is adaptable for operational forensic DNA laboratories.
• This technique offers a powerful tool for forensic investigations involving identical twins.