1Department of Forensic Medicine and Medicolegal, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia
2Department of Forensic Medicine and Medicolegal, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia
3Department of Forensic Medicine and Medicolegal, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia
4Faculty of Medicine, Wijaya Kusuma University, Surabaya, Indonesia
5Forensic Science Study Program, Graduate School of Universitas Airlangga, Surabaya, Indonesia
*Corresponding author: Dr. Wiwin Ida Nur Sri Wahyuni, Department of Forensic Medicine and Medicolegal, Faculty of Medicine, Universitas Airlangga, Surabaya, Indonesia, E-mail: wiwinidans@gmail.com Contact: +6281234308969
Online published on 27 May, 2025.
Specimens for DNA examination are venous, arterial and capillary blood, in addition to sperm, vaginal swabs, buccal swabs and bones. Buccal swab examination can be a good option, comfortable, and relatively easier to perform. The FBI published 13 loci for DNA identification test. Among STR markers, tetranucleotide repeats are more popular.
This is a laboratory experimental research using times series method, from March 2022 to April 2022 at the Forensic Medicine Installation of Dr Soetomo Hospital and the Human Genetics Laboratory of the Tropical Disease Institute, Airlangga University, Surabaya. Population were samples of buccal swab from bodies caused by natural causes death from inpatient installations. The research samples were stored in the refrigerator on the 7th, 20th and 40th day. Kruskal Wallis and the Mann Whitney test were used.
The highest and lowest mean of DNA purity was found on day 40(1.62 μg/dl) and day 1(1.52 μg/dl), respectively. The highest and lowest mean of DNA quantity was found on the 7th day (158.12 μg/dl) and 20th day (112.53 μg/dl). There is no significant difference in the DNA quantity (p=0.761) and DNA purity (p=0.483) based on the storage time. There was no influence on the length of storage on the quality of DNA according to CODIS STR locus. In this study, D12S391, D2S441, D10S1248, D1S1656, D22S1045, and D2S1338 loci were evaluated.
DNA amplification requires DNA purity (λ260/λ280 ratio 1.5 - 2), DNA content, and adequate quality of the DNA. The six loci were chosen as recommended by the FBI with their high discriminatory power. DNA degradation is mostly caused by environmental exposure. Other causes are short chromosome loci and the telomerase process.
There was no association between the duration of buccal swab storage on the quality of DNA according to the STR locus examination.
Buccal Swab, Short Tandem Repeat, DNA Content, DNA Purity
