Introduction
DNA profiling is an odd identification genetic passport that carries information about several dozen genome regions belonging to one person. DNA profiling analyzes the number of repeating elements in a selected area of the genome. The repeating part is called a tandem repeat, and the amount is variable. The control sample is analyzed to create a DNA profile of the person using one of the methods described below. The paper aims to determine the importance of genetic variation in sequences in DNA profiling using specific techniques.
Restriction Fragment Length Polymorphism (RFLP)
The primary strategy for elucidating hereditary qualities utilized for DNA profiling is RFLP analysis. The DNA fragments have different sizes due to varieties between the DNA sequences of diverse individuals, and these particles are isolated based on estimates utilizing gel electrophoresis. One large piece will be detected, corresponding in length to the DNA sequence between two adjacent constant restriction sites for the same endonuclease (Moustafa et al., 2017). The primary identification of polymorphic restriction sites linked to specific genes is possible only if appropriate DNA probes are available. For this purpose, a wide range of endonucleases is used to restrict genomic DNA isolated from a group of unrelated individuals.
Polymerase Chain Reaction (PCR)
The PCR, as the DNA replication, restricts it to the specific DNA sequence. PCR is a technique for copying particular regions of DNA, and isolating DNA from cells occurs for the sample to proceed (Alamoudi et al., 2018). Double-stranded DNA fragments equal in length to the distance between the two primers begin to accumulate after the third cycle. Their number is doubled after each period until the synthesized particles correspond to the original piece, limited by primers. Besides, PCR is carried out in an amplifier, a device that provides periodic cooling and heating of tubes, usually with an accuracy of at least 0.1 ° C. A high-boiling oil was added to the test tube to avoid evaporation of the reaction mixture.
Short Tandem Repeats (STR)
This method analyzes regions with a high degree of polymorphism, which has short repetitive DNA sequences. Since different people have different numbers of repeating units, these pieces of DNA can be used to differentiate between individuals. Specific oligonucleotide primers are selected to the genome regions, and the corresponding DNA fragments are amplified using PCR (Byard & Payne-James, 2015). Therefore, for human identification purposes, it is essential to have DNA markers that exhibit the most significant possible variation, or the number of less polymorphic markers that can be combined to obtain the ability to distinguish between samples.
References
Alamoudi, E., Mehmood, R., Albeshri, A., & Gojobori, T. (2018). DNA profiling methods and tools: A review. In International Conference on Smart Cities, Infrastructure, Technologies and Applications. Springer, 216-231.
Byard, R., & Payne-James, J. (2015). Encyclopedia of forensic and legal medicine. Academic Press.
Moustafa, G. G., Abd-Elhakim, Y. M., & El Sharkawy, N. I. (2017). Genetic profiling of equid hybrids using PCR-RFLP and Partial Sequence Analysis of cytochrome b gene: Forensic implication. Journal of Equine Veterinary Science, 54, 37–41.