Introduction: Every disaster is unique and involves interplay of different factors and circumstances such as nature of disaster, number of victims and extent of body fragmentation that ultimately challenges the disaster response planning. Sample preference for DNA analysis can help in proper management of the disaster .Since a disaster is a chaotic environment that can complicate effective identification of the remains. With some planning, and proper sample selection we can reduce stress for those involved in the identification process thus increasing the probability that all recovered samples are identified.
Aim of the Work: To recognize and decide which human tissue is preferred over the other for DNA tests for human identification for available samples saved from different environmental disasters .Therefore we can decide which sample is preferred over the other if available. , Based on the DNA yield obtained from different human tissues.
Materials and Methods: This cross sectional laboratory based study was conducted at the Egyptian Forensic Medicine Authority (EFMA) at Sayda Zaynab. From May 2016 to April 2017 and tested using manual Qiagen extraction kit or Qiagen automated kit using EZ1.
Extracted DNA was then quatified using Quatifiler® Human DNA Quatification kit by Step one Real Time PCR.
Samples were amplified using AmpFlSTR R Identifiler R plus PCR Amplification Kit (Life Technologies Applied Biosystems). Amplified PCR products were run electrophorethically on a 3130xl or 3500 Genetic Analyzer (Life Technologies Applied Biosystems)
Results: Comparison between different tissues recovered from the site of different disasters showed that dry blood stain have better DNA(Deoxyribonucleic acid) yield and STR(Short Tandem Repeat ) results followed by fresh tissue. Moreover cartilage samples are preferable to bone samples concerning DNA yield and STR results. Finally skin followed by teeth had the least DNA yield.
Conclusion: During sample selection of collected tissue parts and fragments it is preferable to get a dry blood sample if available , if not try to select fresh muscle tissue if not available search for hair with roots then selection of cartilage gave better results than bone concerning DNA yield and STR results leaving skin then teeth as the last choice.