Assessment of The Role of Blood Group Systems and Three DNA Loci (Alu Tpa-25, Humfes / Fps and Humf13ai) in Paternity Testing in a Sample of Egyptian Population

Abstract

A panel of 10 genetic markers has been applied for paternity testing in 51 Egyptian families. The panel included 7 blood group systems (ABO, RI, MNSs, Duffy. Lewis, Kell. & Kidd). und 3 DNA loci (Ali TPA - 25, HUMFES / FPS, & HUMFI3A1). The trio in each family consisted of the mother, the child and the legal or alleged father. The families were studied as 3 groups of statistical significance: The 1st 40th family group in which paternity of legal fathers was tested despite the lack of any suspicion of paternity dispute (expected low probability of disputed paternity), the 41st. 57st family group in which paternity of legal fathers was tested due to strong suspicion of paternity dispute (expected higher probability of disputed paternity), and the 1st – 51st family group in which paternity of 10 known foreign men (to represent alleged fathers with 100% true paternity dispute) was randomly tested in the 57 families of the study. The study included determination of blood groups by the agglutination method and analysis of DNA loci by agarose gel electrophoresis after DNA extraction and amplification by polymerase chain reaction. Exclusion of paternity was concluded from the knowledge of modes of inheritance of the study markers, and probability of paternity (inclusion of paternity) was calculated from the studied gene frequencies after gene typing of the study population. Results of the study showed that the DNA loci were better than blood group systems in exclusion and inclusion of paternity, though both failed to exclude all the alleged fathers or to give reliable values of probability of paternity. The Lewis, Kell, and Kidd blood groups were nearly of no value in paternity testing whereas the polymorphic DNA loci (HUMFES / FPS und HUMF13A1) provided the best results. Some true disputed fathers were excluded by single markers only rising the importance of such exclusion which should be considered seriously and cautiously. Its reliability should be scrutinized, and it may be necessary to examine more markers. It has been concluded that the study panel of 10 genetic markers was not adequate in excluding or proving paternity for all test cases, and that the polymorphic markers provide better resulting should rely upon adequate number of the most valuable genetic markers, and regulatory rules regarding reliable paternity exclusion or inclusion parameters are mandatory, as well as strict application of quality control parameters to the concerned laboratories.