Genomic "dactyloscopy" with the use of bacteriophage M13 as a DNA probe (the expertise of material evidence and personal identification)

In this article the authors give a scientific evaluation of genetic dactyloscopy method in which the sites of human chromosomal DNA, possessing structural polymorphism, act as genetic markers. Technology of genome "dactyloscopy" including both the series of standard conventional methods and new methods is presented. The method is highly sensitive and requires small amounts of material for investigation. A practical case is described when genome "dactyloscopy" gave positive results which led to a conclusion on suspect's involvement in the crime.     

Laboratory evidence of unsuspected parental consanguinity among cases of disputed paternity

A search was conducted to find evidence of possible incestuous unions between the biologic parents of children involved in 2500 paternity cases. Suspicion was raised when either (1) a mother and her child possessed identical HLA phenotypes, or (2) the child appeared to be possibly homozygous for one maternal haplotype (i.e., one of the child's HLA haplotypes was a blank). These mother-child HLA-haplotype dualisms (MHDs) occurred in 5% of all cases. Frequency of exclusion of the accused men in cases demonstrating MHD, was compared with the remaining paternity cases.No significant difference was found in overall exclusion rates between MHD cases and controls when exclusion produced by HLA and red cell antigen systems were observed. However, there was a greater rate of exclusion in MHD cases when comparing exclusions produced by red cell antigen systems regardless of whether HLA tests excluded paternity (p < 0.025). MHD cases involving teenaged mothers differed from control cases in frequency of exclusion of paternity only on the basis of red cell antigen phenotyping (p < 0.005).The HLA system's usefulness in paternity testing is diminished when there is MHD; multiple, independently-inherited systems are relatively more useful in these circumstances.The search method detects only half of potential incest cases; proof of incest requires more extensive testing for homozygosity among other polymorphisms. Since calculations of likelihood of paternity are inappropriate in cases involving close consanguinity, detection and follow up studies are important.Data suggest that one-fifth of MHD cases may involve first degree consanguinity and that the incest rate among paternity cases may be as high as 2%.     

The primary investigation of material evidence and the evaluation of its suitability for expert biological identification by genomic "dactyloscopy"

Use of DNA "fingerprinting" method for biological analysis of material evidences exhibit new potentials for making concrete expert conclusions. But such expertise is time consuming and difficult to perform that's why it is important to evaluate fitness of expert material for DNA fingerprinting at early stages of object investigation. Method of preliminary treatment of objects sent for DNA fingerprint expertise in case of sexual assault is suggested and tested. This method allows one to evaluate objects easily from the standpoint of possibility to perform such investigation.     

Utility of HLA and six erythrocyte antigen systems in excluding paternity among 500 disputed cases

Six erythrocyte antigen systems and the HLA system were evaluated to establish their practical value in 500 cases of disputed paternity. The actual results were very close to predicted values. HLA testing is expected to detect 92% and red cell testing is expected to detect 67% of men falsely accused in paternity suits. The findings of this study show that HLA detected 94% and red cell testing detected 69% of 107 men falsely accused in 500 paternity cases. In order of sensitivity, Rh, MNSs, and ABO were the most useful erythrocyte marker systems. There were six out of 107 cases in which exclusions would have been undetected if red cell typing had not been performed. Five of the six cases involved "common" HLA haplotypes.     

The use of genomic "dactyloscopy" for the diagnosis of monozygotic twins

Possibilities of gene identification expertise for the solution of problem on mono- or dizygotic origin of twins were demonstrated. It was shown that DNA printing method makes it possible to differentiate mono- and dizygotic twins in complicated cases.     

DNA profile evidence in complex disputed paternity cases: The analysis of 300 real cases

In disputed paternity cases where the putative father is unavailable DNA from one or more of his relatives could be used. However, interpreting results is often difficult, because of the partial information regarding the parental genotype obtained from his relatives. We analyzed results obtained in 300 real paternity cases performed through close relatives of the real father (sib, half-sibs, one grandparent and/or uncle). DNA was typed with PowerPlex (Promega) and the LR estimated with the Software BDGen. As expected the higher LR values were achieved with sibs and half-sibs (in such cases where his/her mother was available for testing). The LR values were tight related to the number of uninformative loci, which varied between 0 and 13. In 10% of the reviewed cases, 10 or more non-informative loci were observed; all of them associated LR values below 0.01. Thus, providing evidence in favor of no relatedness.     

Introduction of a standardized "paternity index" for the statistical evaluation of blood group findings in paternity testing

The introduction of a standardized paternity index (PI) for the statistical evaluation of blood group findings in cases of disputed paternity is proposed and explained. By using the PI $\text{X}\text{Y}$ as parameter, it is not necessary to give the information of the probability of paternity in percent. The PI includes the full information of the blood group findings. In addition to that, by using the suggested standardization based on the probabilities of error according to Schulte Mönting and Walter the test volume is also taken into account. The interpretation of the mathematical result is given by verbal predicates, the limitations of which are orientated by the verbal predicates for the probabilities of error according to Schulte Mönting and Walter, published by us elsewhere. Besides the essential fact that the test volume is taken into account, the most important advantage of this procedure is that the mathematical result is involved in the court decision only by the PI (which is free of any valuation) and its verbal predicate and not by sometimes relatively high percentages, which may be misunderstood by laymen.