Chapter 20A Forensic genetics: From classical serological genetic markers to DNA polymorphisms analyzed by microarray technology

Abstract

This chapter discusses forensic genetics classical serological genetic markers to deoxyribo nucleic acid (DNA) polymorphisms analyzed by microarray technology. Forensic genetics can be defined as the application of genetics for the resolution of legal conflicts. Paternity testing, criminal casework and identification of human remains are the types of forensic genetic expertise, which are most commonly requested by judicial authorities and citizens. In earlier times, all the forensic genetic casework was performed using classical serological genetic markers. Blood groups, HLA and polymorphic proteins and enzymes were used for solving forensic genetic casework using immunological and electrophoretic methodologies. Because of the fact that the polymorphic proteins and enzymes are infrequent, it is necessary to obtain as much information as possible. For this reason, sophisticated electrophoretic methods, such as isoelectric focusing, immobilines or hybrid isoelectric focusing are developed and applied. The discovery of polymorphism in repetitive DNA has had a tremendous impact on forensic genetics. DNA typing has advantages over traditional proteins, first of all, because it is more informative and can be analyzed in minute or degraded material since DNA is physically much more resistant to degradation than proteins. Nowadays, DNA analysis has become the standard method in forensic genetics as it is currently used by most of the labs for the majority of forensic genetic expertise and especially in criminal forensic casework (stain analysis and hairs) and identification.