Date of Award
Spring 5-2020
Document Type
Thesis
Degree Name
Master of Science (MS)
Department/Program
Forensic Science
Language
English
First Advisor or Mentor
Lissette Delgado-Cruzata
Second Reader
Martin Rivas
Third Advisor
Mechthild Prinz
Abstract
Conventional STR typing, commonly used in forensics for human identification, poses a problem in criminal cases and paternity disputes involving monozygotic (MZ) twins because they share identical DNA sequences. To date, no routine method is available in forensics to differentiate between individuals of MZ pairs. Recently, epigenetic methods measuring differential DNA methylation patterns have been applied to MZ twin differentiation. In this study, we investigated the potential to identify MZ twins using a previously identified DNA methylation site in chromosome 3, cg18562578, in a sample of 129 MZ and 37 dizygotic (DZ) twin pairs. We used bisulfite converted saliva DNA and a 2-step methylation-specific qPCR method to determine DNA methylation at this site. We investigated differences between MZ and DZ twins as well as within MZ twin pair differences. We found that MZ and DZ twin pair differences were not statistically significant (0.39±0.29 vs 0.46±0.41, p-value=0.38) suggesting that DNA methylation at this site in the genome is not directly related to genetics. In addition, DNA methylation differences between MZ twins in a pair were found to be statistically significant (0.39±0.30 vs 0.78±0.29, p-value=0.00001). However, for 22% of the MZ pairs with DNA methylation differences below 0.1, there is no statistically significant difference to allow for discrimination. While more research needs to be conducted, this study highlights the potential of DNA methylation markers in the discrimination of MZ twins using saliva DNA
Recommended Citation
Robinson, Dino O., "Discrimination of Monozygotic Twins using DNA methylation levels of one CpG site at Chromosome 3" (2020). CUNY Academic Works.
https://academicworks.cuny.edu/jj_etds/141
Included in
Forensic Science and Technology Commons, Genetics Commons, Molecular Biology Commons, Molecular Genetics Commons