Date of Award

Summer 8-23-2019

Document Type

Thesis

Degree Name

Master of Science (MS)

Department/Program

Forensic Science

Language

English

First Advisor

Mechthild Prinz

Second Reader

Lissette Delgado-Cruzata

Third Advisor

David Fisher

Abstract

The main focus of this project was to investigate the protein and DNA components in both sebaceous and eccrine fingerprints. This study investigated the relative content of DNA and proteins in eccrine fingerprints to sebaceous fingerprints. All volunteers were instructed to wash and dry their hands prior to depositing parallel thumbprints. Twenty volunteers were instructed to touch their face to produce sebaceous prints, and 5 volunteers were instructed to wear gloves over a heat source to produce sweaty or eccrine prints. Microscopy was used to score the cellular debris of the right fingerprint on a scale of 1-4 based on density of cellular debris. The score was then compared to the DNA yield and proteins detected in the left fingerprint(s). The results of the study illustrated that sebaceous samples had an average DNA yield of 1101.4 ± 1344.0 pg and eccrine samples had an average DNA yield of 131.7 ± 219.5 pg. The difference in DNA yield between the two sample types was significant (p=0.023). The sebaceous samples (n=20) had an average count of 26 ± 22 proteins, and the eccrine samples (n=5) had an average count of 39 ± 20 proteins. The difference in the number of proteins detected was not significant (p=0.153). The sebaceous samples had better STR quality resulting in 75% full profiles compared to the 20% full DNA profiles of eccrine samples. Linear regression results indicate a lack of correlation between cellular debris scores and DNA yields in sebaceous samples (R=0). A strong correlation between the cellular debris and DNA yield in eccrine samples (R=0.80) needs to be confirmed with more samples. Linear regression results show a moderate correlation between the cellular debris and number of proteins detected for sebaceous and eccrine samples (R=0.39, 0.55, respectively). The results of this study provide additional information about donor variability/shedder status, and the content of DNA and proteins in fingerprint samples.

Available for download on Monday, February 24, 2020

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