Effects of various bodily fluid mixtures on premature lysis of spermatozoa during differential extraction

• Main Author: Liventseva, Natalia
• Language: en_US
• Published: Boston University 2015
• Online Access: https://hdl.handle.net/2144/12486

Thesis (M.S.)--Boston University PLEASE NOTE: Boston University Libraries did not receive an Authorization To Manage form for this thesis or dissertation. It is therefore not openly accessible, though it may be available by request. If you are the author or principal advisor of this work and would like to request open access for it, please contact us at [e-mail]. Thank you. === Bodily fluid mixtures are commonly collected during crime scene processing. When semen is suspected to be present, laboratory techniques are employed to separate the sperm DNA from the non-sperm fraction. The differential extraction is optimized to minimize premature lysis of spermatozoa during the first incubation while still achieving complete epithelial cell lysis. It was previously found that proteinase K concentration, SDS concentration, incubation duration and temperature have no significant effect on sperm cell recovery, suggesting that the differential extraction procedure itself is robust [1, 2]. The aim of this study was to determine whether dehydration or use of saliva as the source of epithelial cells is contributing to premature spermatozoa lysis during the differential extraction technique. It was discovered that under all conditions tested, complete epithelial cell lysis was accomplished without significant amount of spermatozoa DNA loss. All sperm samples when mixed with blood contained significantly less premature sperm cell lysis than when mixed with saliva. It is suspected that early lysis of sperm could be sample or bodily fluid dependent and not due to dehydration.