Genetic variation and DNA markers in forensic analysis

Abstract

In this review, we highlighted the DNA markers and their applications in forensic medicine which included the study of genetic variation or polymorphism, markers for genetic variation, types of variation, diallelic polymorphisms (SNPs and Indels), haplotypes, autosomal short tandem repeat (STRs), Y-chromosome short tandem repeat (Y-STRs) and Y chromosome. This is a useful tool for tracing human evolution, analysis of Y-chromosomal microsatellite haplotypes in globally human populations, organization of the human mitochondrial genome, and mitochondrial coding region as a source for variability and interpretation of sequence data. The light has been focused and directed in this study to establish the basic forensic genetic information, knowledge, data and statistics which might be so ultimately helpful practically in forensic science and criminology and to let evaluate and present the DNA weight evidences in medico-legal institute and courts of law.

Phytochemical screening of methanolic dried galls extract of Quercus infectoria using gas chromatography-mass spectrometry (GC-MS) and Fourier transform-infrared (FT-IR)

“…The GC-MS analysis of the plant extract was made in a Agilent 7890 A instrument under computer control at 70 eV Imad et al, 2014a). About 1 μl of the methanol extract was injected into the GC-MS using a micro syringe and the scanning was done for 45 min.…”

Analysis of bioactive chemical compounds of Aspergillus niger by using gas chromatography-mass spectrometry and fourier-transform infrared spectroscopy

“…Data were analyzed using analysis of variance (ANOVA), and differences among the means were determined for significance at P < 0.05 using Duncan's multiple range test (by statistical package for the social sciences (SPSS) software) Version 9.1 (Imad et al, 2014b).…”

“…Metabolites was separated from the liquid culture and evaporated to dryness with a rotary evaporator at 45ºC. The residue was dissolved in 1 ml methanol, filtered through a 0.2 μm syringe filter, and stored at 4ºC for 24 h before being used for gas chromatography-mass spectrometry (GC-MS) (Imad et al, 2014a). The identification of the components was based on comparison of their mass spectra with those of NIST mass spectral library as well as on comparison of their retention indices either with those of authentic compounds or with literature values.…”

Determination of metabolites products by Cassia angustifolia and evaluate antimicobial activity

“…About 1 μl of the methanol extract was injected into the GC-MS using a micro syringe and the scanning was done for 45 min. As the compounds were separated, they eluted from the column and entered a detector which was capable of creating an electronic signal whenever a compound was detected (Imad et al, 2014a;Kareem et al, 2015). The greater the concentration in the sample, the bigger was the signal obtained which was then processed by a computer.…”