Abstract
There is high demand for forensic age prediction in actual crime investigations. In this study, a novel age prediction model for saliva samples using methylation-sensitive high resolution melting (MS-HRM) was developed. The methylation profiles of ELOVL2 and EDARADD showed high correlations with age and were used to predict age with support vector regression. ELOVL2 was first reported as an age predictive marker for saliva samples. The prediction model showed high accuracy with a mean absolute deviation (MAD) from chronological age of 5.96 years among 197 training samples. The model was further validated with an additional 50 test samples (MAD = 6.25). In addition, the age prediction model was applied to saliva extracted from seven cigarette butts, as in an actual crime scene. The MAD (7.65 years) for these samples was slightly higher than that of intact saliva samples. A smoking habit or the ingredients of cigarettes themselves did not significantly affect the prediction model and could be ignored. MS-HRM provides a quick (2 hours) and cost-effective (95% decreased compared to that of DNA chips) method of analysis. Thus, this study may provide a novel strategy for predicting the age of a person of interest in actual crime scene investigations.
Highlights
Traditional polymerase chain reaction (PCR), which is a universal and cost- and time-effective method, may be the key technique for the realization of forensic age prediction in actual crime investigations owing to its many advantages[18]
We developed an age prediction model for blood samples by analysing methylation profiles of the promoter regions of ELOVL2 and FHL220
Bisulphite PCR primers were newly designed for these 10 markers for HRM, though only EDARADD showed site-specific bisulphite PCR amplification due to the sequence simplicity of bisulphite-modified DNA
Summary
Traditional polymerase chain reaction (PCR), which is a universal and cost- and time-effective method, may be the key technique for the realization of forensic age prediction in actual crime investigations owing to its many advantages[18]. During the writing of this manuscript, Hong et al developed an age estimation model for saliva samples[29] All of these methods suffer from the abovementioned difficulties in practical use. We report a practical age prediction method that involves analysing the methylation status of ELOVL2 and EDARADD via MS-HRM of saliva samples. Saliva DNA was extracted from cigarette butts, and age prediction was performed as in an actual crime scene for the first time ever. This HRM-based method has great potential for predicting age and is quite useful, especially when DNA data for the person of interest are not recorded in criminal databases
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
