Introduction: DNA typing is one of the most crucial molecular biology tools used in forensic investigations, paternal identification, genetic testing, and archaeological studies. However, DNA integrity tends to be compromised with time when they are exposed to various environmental factors like heat, moisture, air, and UV radiation. Degradation of DNA drastically affects the downstream tests done and it becomes difficult to retrieve reliable data from degraded samples. Therefore, studying DNA degradation from biological samples is important for its utilization in DNA profiling.

Aims and Objectives: In our current study, we aimed to estimate the rate of DNA degradation with time in biological fluids, especially blood and saliva, under regular environmental conditions.

Method: We extracted genomic DNA from blood and saliva samples after storing them in natural environmental conditions for different time periods. We evaluated four extraction methods; Salt-Out, Chloroform: Isoamyl alcohol, Methanol, and Phenol: Chloroform: Isoamyl Alcohol. UV-Spectrophotometry and RT-PCR quantitative analysis were used to evaluate DNA concentration.

Result: The degradation rate of genomic DNA from blood and saliva increased over time. Using RT-PCR, blood DNA concentration declined from 74.534 ng/10µl on day 1 to 54.429 ng/10µl by day 30, with consistent UV-Spectrophotometry results. Saliva DNA showed a decrease from 53.926 ng/10µl on day 1 to 29.106 ng/10µl by day 30, with both RT-PCR and UV-Spectrophotometry results showing gradual declines every 5 days.

Conclusion: Our work highlights the practicality of these straightforward and efficient DNA extraction approaches for forensics, diagnostics, and genotyping. The results indicate the critical need for timely sample processing to limit DNA degradation. Our work helps provide a key understanding of the storage and handling of biological samples within molecular biology and forensic investigations by assessing the degradation rate and measuring DNA levels at multiple time intervals.

KEYWORDS: DNA, DNA Profiling, Forensic Studies, DNA Extraction, RT-PCR, UV-Spectrophotometry, Gel Electrophoresis.