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Procedure 6102Santa Ana Police Department Santa Ana PD Procedures Manual Copyright Lexipol, LLC 2021/05/05, All Rights Reserved. Published with permission by Santa Ana Police DepartmentDNA AND BIOLOGICAL EVIDENCE - 1DNA AND BIOLOGICAL EVIDENCE 6102.1 PURPOSE This procedure provides guidelines for processing for DNA and biological evidence. Deoxyribonucleic acid, commonly referred to as DNA, is a molecule responsible for carrying genetic material. DNA is unique to an individual, with the exception of identical twins. This makes DNA a potentially useful tool for identification purposes. 6102.2 PERSONAL PROTECTIVE EQUIPMENT When evidence is handled, there is a possibility of contamination of the evidence, and the possibility of the handler being exposed to any substances present. Every reasonable effort should be made to minimize these contamination and exposure possibilities. Proper use of personal protective equipment (PPE), as detailed below, is the first line of defense against possible contamination and exposure. An appropriate mask should be worn. The mask should be donned prior to donning gloves so that any contact with hair or skin does not contaminate the gloves. A dust mask is typically sufficient when processing for possible biological evidence. Appropriate gloves should be worn when handling evidence items in order to preserve possible biological evidence, and when processing items for possible biological evidence. Personnel should make every reasonable effort to change gloves frequently when processing for possible biological evidence. This minimizes the risk of cross-contamination due to the gloves transferring potential biological evidence. It is recommended a ‘base’ pair of gloves be worn, with another layer of gloves on top. This facilitates changing the top layer of gloves with frequency, while the ‘base’ layer of gloves remains and helps protect against possible contamination. Certain individuals have been found to ‘shed’ more DNA than others, and as such, the wearing of long-sleeved shirts or disposable protective sleeves is recommended when appropriate. 6102.3 SWABBING TECHNIQUE Sterile single-use swabs are the primary method for the collection of most DNA evidence located at crime scenes, on evidence items, or on involved subjects. Swabbing for DNA evidence is typically completed in the following manner. Adjustments can be made depending on the specific circumstances of the situation. 1.Don appropriate PPE (at minimum gloves and mask). 2.Label the exterior of the individual packaging sleeve for each sterile single-use swab to be collected. 3.Open the packaging sleeve and, using the handle end, remove the swab from the packaging. 4.DO NOT LET THE SWAB HEAD COME INTO CONTACT WITH ANY AREA/ITEM BUT THE INTENDED SAMPLE AREA/ITEM. Santa Ana Police Department Santa Ana PD Procedures Manual DNA AND BIOLOGICAL EVIDENCE Copyright Lexipol, LLC 2021/05/05, All Rights Reserved. Published with permission by Santa Ana Police DepartmentDNA AND BIOLOGICAL EVIDENCE - 25.If swabbing a dried sample or processing for touch DNA, lightly moisten the tip of the swab head with distilled or sterile water. 6.Vigorously rub the swab over the area or stain in question. 7.Return the swab, head first, into its individual packaging sleeve. 8.Allow the swabs to completely air dry. 9.Individually packaged swabs can be placed into paper evidence packages and stored in secured evidence freezers 10.Individually packaged swabs collected from similar areas/items of evidence may be packaged together into one paper evidence package. 11.Individually packaged swabs from biological fluid samples should be packaged in different paper evidence packages from touch DNA samples. 6102.4 BODILY FLUIDS Nearly every cell in the body contains DNA, and as such, many bodily fluids, along with tissues, contain DNA. Blood, saliva, semen, and vaginal fluid are among the bodily fluids most commonly located at crime scenes, however, a search should always be made for any potential bodily fluid that may contain biological evidence. 1.Blood may be present at scenes, on items of evidence, or on involved subjects. Blood may be liquid or dried. In most circumstances, photographs should be taken of the blood prior to collection/processing. Liquid blood should be collected using sterile single-use swabs (per the above recommendations). If the liquid bloodstain is large (i.e. pooled blood), liquid blood sample swabs should be collected from the outer edges of the stain. Smaller stains may be swabbed in their entirety (a)Dried blood can be collected using a sterile single-use swab moistened with distilled sterile water. Dried blood can also be scraped, with the flakes collected in a weigh paper bindle. 2.Biological fluids may be present at scenes, on items of evidence, or on involved subjects. If the biological fluid sample is a wet stain, it can be collected using sterile single-use swabs. If a biological fluid sample is a dried stain, it can be collected using a sterile single-use swab moistened with distilled sterile water. (a)When biological fluid samples are located on clothing or other porous surfaces, the entire object, or a sufficient representative cutting if an object is too large to collect, can be collected and booked for processing at the Orange County Crime Lab. Examples may include items such as cigarette butts, chewed gum, underwear, carpet, etc 6102.5 TRACE/TOUCH DNA In addition to bodily fluids, trace amounts of DNA evidence can also be transferred and left behind by touch. This biological evidence is commonly referred to as trace