Date of Award
Spring 5-2021
Document Type
Thesis
Degree Name
Master of Science (MS)
Department/Program
Forensic Science
Language
English
First Advisor or Mentor
Mechthild Prinz
Second Reader
Nicholas Petraco
Third Advisor
Grace Axler-DiPerte
Abstract
Trace DNA evidence may be discovered at a crime scene after having been deposited by a person of interest via active or passive transfer. Based on previous studies, passive transfer of one’s DNA is influenced by their shedding propensity, or probability of depositing a detectable amount of DNA through touch. Determining the shedding propensity of a person of interest can aid in trace DNA interpretation in forensic casework. This study explored STR profile quality and the presence of a DNA mixture for different skin surface locations, including fingertips before and after handwashing. As expected, unwashed fingers showed a higher prevalence of mixtures than washed fingers. Hand dominance showed no significant effect on right versus left finger STR profile quality. However, right-handed participants exhibited a higher mixture prevalence for samples obtained from their dominant hand. Shedding propensity was determined based on STR profile quality and the number of expected alleles detected from washed finger samples only. Three individuals were high shedders (10.7%), 18 individuals were intermediate shedders (64.3%), and seven individuals were low shedders (25.0%). No trend was seen for shedding propensity, profile quality, or mixture status based on biological sex. STR profile quality can be affected by various factors and future research will combine the use of STR results with quantification data to develop an alternative method of predicting shedding propensity.
Recommended Citation
Trapani, Genevieve, "Determination of Human Shedding Propensity Based on STR Results" (2021). CUNY Academic Works.
https://academicworks.cuny.edu/jj_etds/183
Included in
Forensic Science and Technology Commons, Genetics Commons, Molecular Biology Commons, Molecular Genetics Commons