PARENTAL TESTING IN THE FORENSIC MEDICINE INSTITUTE OF POZNAN UNIVERSITY OF MEDICAL SCIENCES

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1 Medical News 2013, 82, 6, PIOTR KORDEL 1, MAŁGORZATA KORALEWSKA-KORDEL 2 PARENTAL TESTING IN THE FORENSIC MEDICINE INSTITUTE OF POZNAN UNIVERSITY OF MEDICAL SCIENCES USTALANIE OJCOSTWA W ZAKŁADZIE MEDYCYNY SĄDOWEJ UNIWERSYTETU MEDYCZNEGO W POZNANIU W LATACH Laboratory of History of Public Health and Social and Health Policy, Chair of Social Sciences Poznan University of Medical Sciences, Poland Head: prof. Michał Musielak 2 Department and Institute of Forensic Medicine, Poznan University of Medical Sciences, Poland Head: Czesław Żaba, MD, PhD Abstract Introduction. Stating or denying the identity between the biological and legal parentage has been a problem for centuries. Not until the latter half of 20th century, thanks to advances in medical sciences, this problem couldn t be solved. The classic serological analysis, the HLA system analysis and DNA analysis enabled people to exclude or confirm paternity. Aim. Presentation of the structure of non-paternity events in expert opinions provided by the Forensic Medicine Institute of Poznan University of Medical Sciences in the years , judging the influence of the method used for parental testing on the percentage of non-paternity events and presentation the influence of demographic changes in Poland on the number of paternity tests run by the Forensic Medicine Institute of Poznan University of Medical Sciences. Material and methods. The research material were the results of the paternity test conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences in the years : 4387 serological test, 679 HLA system tests and 1252 DNA analyses. Results. The percentage of non-paternity events in serological test in the years reached 24.25%. In HLA system analyses in the years non-paternity events were 14.29% and in DNA analyses they were 20.85%. Conclusions. The method used for parental testing does not influence the non-paternity events percentage but the demographic changes had influenced the number of parental tests run by the Forensic Medicine Institute of Poznan University of Medical Sciences. KEY WORDS: parental testing, serological analysis, HLA analysis, DNA analysis. Streszczenie Wstęp. Ustalenie tożsamości między ojcostwem biologicznym i prawnym przez wieki było problemem nierozwiązywalnym. Dopiero w drugiej połowie XX w., dzięki postępom w naukach medycznych, udało się rozwiązać ten problem. Klasyczna ekspertyza serologiczna, badania układu HLA i analiza DNA pozwoliły na wykluczenie, a następnie potwierdzenie ojcostwa. Cel. Przedstawienie struktury wykluczeń ojcostwa w ekspertyzach Zakładu Medycyny Sądowej UM w Poznaniu w latach , ocena wpływu stosowanej metody analizy na procent wykluczeń oraz przedstawienie wpływu przemian demograficznych w Polsce na liczbę wykonywanych badań w Zakładzie Medycyny Sądowej UM w Poznaniu. Materiał i metody. Materiał badawczy stanowiły wyniki badań ustalenia ojcostwa przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w latach : 4387 ekspertyzy serologiczne, 679 badań układu HLA i 1252 analizy DNA. Wyniki. Odsetek wykluczeń ojcostwa przy zastosowaniu klasycznej ekspertyzy serologicznej wynosił w latach ,25%. W przypadku ekspertyz układu HLA w latach wykluczenia ojcostwa stanowiły 14,29% wyników. Z kolei w wyniku analiz DNA w latach wykluczenia ojcostwa stanowiły 20,85% wyników badań. Wnioski. Stosowana metoda ustalania ojcostwa nie wpłynęła na odsetek wykluczeń w badaniach. Wpływ przemian demograficznych na liczbę badań ustalenia ojcostwa w Zakładzie Medycyny Sądowej UM w Poznaniu jest wyraźnie zauważalny. SŁOWA KLUCZOWE: ustalanie ojcostwa, ekspertyza serologiczna, ekspertyza HLA, analiza DNA. Introduction Each year in Poland courts hear several thousand cases related to the problem of paternity. Those cases concern mainly affiliation and denial of paternity. The trial in those cases in ended by a verdict stating or denying the identity between the biological and legal parentage. The problem of parentage is dated back to the ancient times. The only methods available used for checking whether the man was the biological father of a child

2 422 Piotr Kordel, Małgorzata Koralewska-Kordel were, for many ages, the anthropological methods basing on the physical resemblance between the father and the child, which were an imperfect tool, and the knowledge on the time of conception. The second method was also faulty because promiscuous nature of human beings. The thing that proves best the weakness of those methods is the Roman maxim Mater semper certa est, pater semper incertus est and the legal presumption of legitimacy pater est, quem nuptiae demonstrant, which is also present in Polish family law (art. 62 of the Polish Family and Guardianship Code, Polish Official Journal No ). The advances of medical sciences enabled people to solve the problem of stating the biological paternity. The first method used for exclusion of paternity was the serological expertise. Introduction of the study of blood groups into courtroom practice as an evidence was possible thanks to many discoveries such as Gregor Mendel s inheritance patterns or Karl Landsteiner s distinction of the main blood groups. In 1911 Ludwik Hirszfeld proved that blood groups are inherited according to rules stated by Mendel. Poland was one of the first countries which allowed serological expertise in courts in 1926 professor Jan Olbrycht ran serological test for an alimony trial for a court in Krakow and professor Ludwik Hirszfeld did the same for a court in Warsaw [1]. Through the years the range of serological expertise changed thanks to discovering new serological systems. The Polish Society of Forensic Medicine and Criminology set 11 systems, which were used for serological expertise: AB0, MNSe, Rh, Kell-Cellano, Hp, Gm(1), Gc, Blood Acid Phosphatase, Phosphoglucomutase, D Esterase, GLO I. The efficiency of the classic serological expertise in excluding paternity reached 88% [2]. In the latter half of the 1970 s the HLA system expertise became a legal evidence. The first HLA expertise in Poland was conducted in Poznan in 1980 [3]. The HLA system analysis was used as the 2 nd degree analysis for the classic serological expertise. The excluding power of those two combined methods reached 97% [4, 5]. The 1990 s brought a significant change in paternity testing. The DNA analysis methods developed by A.J. Jeffreys i K. Mullins [6] enabled scientists not only to exclude parentage but to confirm it with the probability reaching 99.99% [7]. Between 1991 and 1997 in the Forensic Medicine Institute of Poznan University of Medical Sciences the DNA analysis was used as the 3 rd degree analysis together with serological and HLA tests. After 1997, due to high costs, the HLA expertise was abandoned and the serological test were run extremely rare because the DNA analysis turned out to be the most effective method. Aim The aims of the article are: Presentation of the structure of non-paternity events in expert opinions provided by the Forensic Medicine Institute of Poznan University of Medical Sciences in the years for the legal trials concerning affiliation and denial of paternity. Judging the influence of the method used for parental testing on the percentage of non-paternity events in the expert opinions provided by the Forensic Medicine Institute of Poznan University of Medical Sciences. Presentation of the influence of demographic changes in Poland on the number of paternity tests run by the Forensic Medicine Institute of Poznan University of Medical Sciences. Material and methods The research material were the results of the paternity test conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences in the years : 4387 serological test, 679 HLA system tests and 1252 DNA analyses. The methods used for serological tests concerning red blood cells group antigens were standard methods using diagnostic serums provided by Biotest, Fresenius, Organon, Bheringwerke, Immuno and Ortho. For marking the antigens of the HLA system a microcytotoxicity tests were used with serums provided by Behringwerke, Biotest, Fresenius and Hintel and a rabbit complement. The DNA analyses were run using DNA hybridization and the polymerase chain reaction with multiplex PCR amplification and analysis of STR DNA Loci by AmpF Identifiler system by Applied Biosystems. Results The standard serological expertise was conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences up to Since test were conducted in which 1064 excluded paternity of the alleged father. As Table 1 shows it were 24.25% of all tests. Depending on year the percentage of non-paternity events varied from 28% to 11.7%. Table 2 presents the percentage of non-paternity events using the HLA system analysis. As it can be seen the exclusion percentage for this method is much lower and reaches 14.29%. It results from the fact that HLA system analysis was used as the II nd degree analysis, that means that it was used when the classic serological test was unable to exclude paternity. Table 3 presents the percentage of non-paternity events for DNA analysis method which reaches 20.85%. Conclusions Analyzing Tables 1, 2 and 3 it is possible to say that the method used for parental testing does not influence the non-paternity events percentage. It seemed that the increase in test sensitivity should produce growth of the parentage exclusion percentage but we observed a significant drop from 24.25% for serological tests to 20.85% for DNA analysis.

3 Parental testing in the Forensic Medicine Institute of Poznan University of Medical Sciences Table 1. Non-paternity events in serological tests conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences Tabela 1. Zaprzeczenia ojcostwa w ekspertyzach serologicznych przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w latach Number of serological tests Number of non-paternity events % of non-paternity events Total Table 2. Non-paternity events in HLA analyses conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences Tabela 2. Zaprzeczenia ojcostwa w analizach HLA przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w latach Number of HLA tests Number of non-paternity events % of non-paternity events Total

4 424 Piotr Kordel, Małgorzata Koralewska-Kordel Table 3. Non-paternity events in DNA analyses conducted in the Forensic Medicine Institute of Poznan University of Medical Tabela 3. Zaprzeczenia ojcostwa w analizach DNA przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w latach Number of DNA tests Number of non-paternity events % of non-paternity events Total Table 4. Illegitimate births in Poland Tabela 4. Urodzenia pozamałżeńskie w Polsce w latach Number of illegitimate births Illegitimate as a percentage of total live births Data from Demographic Yearbooks of Poland published by Central Statistical Offi ce. Opracowanie własne na podstawie roczników demografi cznych GUS.

5 Parental testing in the Forensic Medicine Institute of Poznan University of Medical Sciences Interesting conclusions come from comparing the number of parental tests run in the Forensic Medicine Institute of Poznan University of Medical Sciences with the illegitimate births rate in Poland published by the Central Statistical Office (Główny Urząd Statystyczny). Table 4 illustrates that since 1970 up to 2011 a constant growth of illegitimate births rate can be observed. In 2011 every fifth child was born outside marriage. This could lead to a presumption that the number of court trials related to the problem of paternity should grow and so should the number of paternity tests. But as can be seen in Figure 1 there is no such correlation. What is more, a significant drop can be seen. When it comes to the HLA system analyses (Figure 2) the drop results from introducing the DNA analysis method. But when the classic serological expertise is concerned (Figure 3) a significant difference between 1980 s and 1990 s can be observed. It results from a severe drop of the live birth rate in Poland (Figure 4). Figure 1. Number of paternity test conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences Rycina 1. Liczba ekspertyz w sprawach dotyczących ustalenia ojcostwa w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w latach Figure 2. Number of HLA analyses conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences in cases related to the problem of paternity Rycina 2. Liczba analiz HLA przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w sprawach dotyczących ustalenia ojcostwa w latach

6 426 Piotr Kordel, Małgorzata Koralewska-Kordel Figure 3. Number of serological test conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences in cases related to the problem of paternity Rycina 3. Liczba ekspertyz serologicznych przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w sprawach dotyczących ustalenia ojcostwa w latach Figure 4. Live birth rate in Poland Rycina 4. Urodzenia żywe w Polsce w latach Data from Demographic Yearbooks of Poland published by Central Statistical Offi ce. Opracowanie własne na podstawie roczników demografi cznych GUS.

7 Parental testing in the Forensic Medicine Institute of Poznan University of Medical Sciences Figure 5. Number of DNA analyses conducted in the Forensic Medicine Institute of Poznan University of Medical Sciences in cases related to the problem of paternity Rycina 5. Liczba analiz DNA przeprowadzonych w Zakładzie Medycyny Sądowej Uniwersytetu Medycznego w Poznaniu w sprawach dotyczących ustalenia ojcostwa w latach The more or less constant level of number of DNA analyses run by the Forensic Medicine Institute of Poznan University of Medical Sciences from 2001 to 2011 (Figure 5) may be a result of counterbalance effect which the growth of illegitimate birth rate has on the drop of the total live birth rate. References 1. Turowska B. Badania grupowe krwi w sprawach spornego ojcostwa przeprowadzone w Katedrze i Zakładzie Medycyny Sądowej w Krakowie w latach Archiwum Medycyny Sądowej i Kryminologii, XLVII: Dobosz T, Świątek B. Dochodzenie spornego ojcostwa poprzez badanie polimorfizmu DNA. Post Med Sąd Krym. T. III: Stawarz M, Przybylski Z. Polimorfizm układu HLA locus A, B, C i jego przydatność przy dochodzeniu spornego ojcostwa. Archiwum Medycyny Sądowej i Kryminologii. XXX: Kordel M, Kątniak R, Kordel K. Częstość i struktura wykluczeń ojcostwa w układzie HLA. Post Med Sąd Krym. 1988, T. I: Pepiński W, Janica J. Częstość antygenów HLA ABC oraz częstość i struktura wykluczeń w badaniach spornego ojcostwa w populacji Polski Północno-Wschodniej. Post Med Sąd Krym. 1995; T. II: Mullis KB, Faloona F. Specific synthesis of DNA in vitro a PCR reaction. Methods Enzymol. 155: Bjerie A, Syndercombe D, Lincoln P, Morling N. A report of the 1995 and 1996 paternity testing workshop of the English speaking working group of the International Society for Forensic Haemogenetics. Forensic Sci Int. 90: Correspondence address: Chair of Social Sciences Poznan University of Medical Sciences 79 Dąbrowskiego Street Poznań, Poland phone: kordel@ump.edu.pl