Kamis, 17 Juli 2014





P-013
Population study of small-sized short tandem repeat in Japan and its application to analysis of degraded samples

Asamura H, Tsukada K, Ota M, Sakai H, Takayanagi K, Kobayashi K, Saito S, Fukushima H

Department of Legal Medicine, Shinshu University School of Medicine

Analysis of short tandem repeat (STR) is the most valuable tool for the clarification of personal identity. Recently, several commercial multiplex STR kits are regularly used in forensic practice. However, for some highly degraded samples, analysis of STR by means of the commercial STR kits is practically impossible due to DNA fragmentation and occurrence of PCR inhibitors. Some papers reported that smaller–sized PCR products were effective in analyzing such highly degraded samples. We previously performed multiplex PCR for the TH01, TPOX, CSF1PO, and vWA loci using a newly designed pair of primers that yield smaller fragment, and reported several successful analyses of the degraded samples. In this study the six mini-STR loci (D1S1677, D2S441, D4S2364, D10S1248, D14S1434, and D22S1045), which Coble et al. reported, were investigated in Japanese population. As the result, analysis with use of the six loci demonstrated the moderate degree of polymorphisms in Japanese population. Moreover, it was confirmed that these six loci assays for typing degraded samples were more successful than those of commercial STR kits. Consequently, it was considered that combination analyses of the six mini-STR loci and the four loci, which we previously reported, are highly beneficial in the context of Japanese forensic practice from degraded DNA samples.


P-014
Allele distribution of two X chromosomal STR loci in a population of Sicily
(Southern Italy)

Asmundo A., Perri F., Sapienza D.

Dipartimento di medicina sociale del territorio, Sezione di medicina legale, Università di Messina, Azienda Ospedaliera Universitaria “Policlinico G. Martino”, Via Consolare Valeria 98125 Messina, Italy

Population genetic data for two X-chromosomal STR loci (DXS7423 and DXS9902) were obtained by analysing a population sample (n= 60 males and 60 females) and 43 family trios (showing a probability of paternity and maternity > 99.9%) from Sicily (Southern Italy) by using PCR and PAGE followed by silver staining. Five and four different alleles of DXS7423 and DXS9902 loci were detected, respectively. The allele frequencies of both ChrX markers were in good agreement with Hardy-Weinberg equilibrium. The analysis of the family trios, based on the investigated meiotic events, showed no mutation. The observed eterozigosity of DXS7423 and DXS9902, together with other forensic parameters were determined, so confirmating that these markers are useful tools for parentage testing, mainly in deficiency paternity cases when the disputed son is female.


P-015
Forensic evaluation of three closely linked STR markers in a 13 kb region at Xp11.23

Augustin C1, Cichy R1, Hering S2, Edelmann J3, Kuhlisch E4, Szibor R5

1Institute of Legal Medicine, University of Hamburg, Germany
2Institute of Legal Medicine, Technical University of Dresden, Germany
3Institute of Legal Medicine, University of Leipzig, Germany
4 Institut für Medizinische Informatik und Biometrie, Technical University of Dresden, Germany
5Institute of Legal Medicine, University of Magdeburg, Germany

Searching for markers located in the Xp11 region the sequence of the clone AF196972 was checked for its content of microsatellites. Two tetranucleotide STRs and one trinucleodide STR were tested in respect of their forensic efficiency and registered in the GDB as DXS10076, DXS10077 and DXS10078.
DXS10076 is located 48 065.564 - 48 065.759 kb from the Xptel. DXS10077 and DXS10078 are located further 7.701 kb and 12.879 kb downstream, respectively.
The three STRs differ clearly in their individualization capacity as could be shown in a population sample of 201 male and 151 female Germans. Whereas at Locus DXS10076 10 alleles and at Locus DXS10078 13 alleles could be detected resulting in PIC and HET values of 0.767 and 0.747 (DXS10076) and 0.811 and  0.861 (DXS10078), respectively, the trinucleotide STR DXS10077 consists of 5 alleles leading to much lower PIC (0.492) and HET (0.507) values.
Two paternal mutations were detected at DXS10078 in 150 families with confirmed paternity while no mutations could be found until now at the other two loci.
Theoretically, this cluster could give rise to 650 different haplotypes in the German population. In fact, genotyping of 201 males revealed the presence of 72 haplotypes. Due to their closely linked location the three STRs form a cluster free of recombination. The stability of haplotypes was tested in 90 three-generation families. Hence, the Xp11.23 STR cluster reported here can contribute to solving complex kinship cases. Special aspects such as linkage disequilibrium etc. will be discussed in detail.



P-016
Danger of false inclusion among deficient paternity case

 

Babol-Pokora K, Jacewicz R, Szram S

Department of Forensic Medicine, Medical University of Lodz, Lodz, Poland

Deficient cases, such as motherless cases, are more difficult then standard ones, but a conclusion can still be derived, based on the types of the child and alleged father. More complicated are cases in which the alleged father is unavailable for testing – these are difficult to calculate. But the real problem is when both mother and father are unavailable. Such cases can be burdened with danger of false inclusion.
In our practice we had a deficiency case, in which the alleged father was unavailable, so we had to test his parents. We used Identifiler™ system and there was no exclusion in that case, when we typed the child and his grandparents only. The probability of paternity that we obtained was 99,9 percent. Mother’s typing, however, revealed exclusions in 3 STR loci among the Identifiler™ system. Further researches showed exclusions in 4 STR loci out of 21 tested STR loci.


P-017
IDENTIFILER™ system as an inadequate tool for judging deficient paternity cases

Babol-Pokora K, Jacewicz R, Szram S

Department of Forensic Medicine, Medical University of Lodz, Lodz, Poland


Identifiler™ is known to be one of the most useful multiplex systems for standard paternity testing. But in some cases the mother is unavailable and there can be a problem with obtaining sufficient value of probability of paternity. We typed nine hundred unrelated individuals from Central Poland population (Lodz region), in order to check the usefulness of Identifiler™ for analysis of motherless cases. The most important thing was to compare the evidence value between standard cases (trios) and deficient ones (duos). One hundred and fifty excluding cases and one hundred and fifty including ones were analysed and the results were estimated for trios and duos. Power of exclusion and paternity index were analysed for each locus as well as for the entire set of the fifteen STR markers. Our researches confirmed the usefulness of Identifiler™ system for standard paternity testing, and showed that the minimal probability of paternity that can be obtained, is 99,999 percent. In motherless cases however, the average value of probability of paternity was as low as 99,9 percent. The minimal number of excluding loci among trio cases was four, whilst among duo ones there were events of exclusion in one locus only. That is why Identifiler™ is proper for standard paternity cases, however motherless cases need to be examined more widely.


P-018
Is SGM Plus™ the sufficient system for paternity testing?

Babol-Pokora K, Jacewicz R, Szram S

Department of Forensic Medicine, Medical University of Lodz, Lodz, Poland


SGM Plus™ is one of the multiplex systems commonly used in forensic genetics. It consists of 10 STR loci which can be useful for parentage testing. We present results of typing in nine hundred unrelated individuals from Central Poland population (Lodz region), in order to check the usefulness of SGM Plus™ system for paternity testing. One hundred and fifty excluding cases and one hundred and fifty including ones were analysed in the range of 10 STR loci of SGM Plus™ system and the results were estimated for standard and motherless cases. Power of exclusion and paternity index were analysed for each of ten loci as well as for entire SGM Plus™ set.  Our researches showed that the SGM Plus™ is not sufficient for parentage testing. The minimal number of excluding loci for SGM Plus™ analyses was one among duo cases and two among trio ones and there was an event of false inclusion, which was revealed after Identifiler™ analysis. Additionally the number of excluding loci among twenty seven percent of duo cases was less than four.  The probability of paternity in almost sixty percent of trio cases was 99,99 percent and lower. Additionally the average value of probability of paternity among duo cases was as low as 99,0 percent. That is why we consider SGM Plus™  not to be sufficient for paternity testing among deficient cases as well as standard ones.


P-019
The Beneficial Effect of Extending the Y Chromosome STR Haplotype

Ballard DJ, Khan R, Thacker CR, Harrison C, Musgrave-Brown E, Syndercombe Court D

Centre for Haematology, ICMS, Barts & The London, Queen Mary’s School of Medicine & Dentistry, UK


Y chromosome testing is becoming a more frequently used technique both in criminal and relationship cases.  One drawback with this method however, is the relatively low haplotype diversity when compared with autosomal DNA profiles.  The consequence of this lower diversity is that individuals can present with the same Y-STR haplotype even if they are not closely related. 
During the development of Y chromosome testing there was a scarcity of known Y-STR loci and it is only recently that larger numbers of polymorphic markers have been discovered.  Haplotype diversity is therefore partially compromised in standard forensic Y chromosome testing protocols by the need to use the established markers, not all of which are highly polymorphic.  We have taken a number of the recently discovered highly polymorphic markers and analysed them in addition to the standard set of Y chromosome loci.   Presented here are the allele frequencies for these loci in the British population along with the resulting increase in haplotype diversity associated with their incorporation.  Also detailed is a relationship case that demonstrates the advantages that additional informative Y chromosome loci can confer when used in forensic casework.


P-020
Application of Whole Genome Amplification for Forensic Analysis


Balogh MK1, Børsting C2, Sánchez Diz P3, Thacker C4, Syndercombe-Court D4, Carracedo A3, Morling N2, Schneider PM1, and the SNPforID Consortium

1 Institute of Legal Medicine, Johannes Gutenberg University of Mainz, Germany
2 Institute of Legal Medicine, University of Santiago de Compostela, Spain
3Department of Forensic Genetics, Institute of Forensic Medicine, University of Copenhagen, Denmark
4Centre for Haematology, ICMS, Barts and The London, Queen Mary's School of Medicine and Dentistry, UK
www.snpforid.org

Fundamental to most forensic analysis is the availability of genomic DNA of adequate quality and quantity. To perform a multitude of genetic analysis and assays requires sufficiently large amount of template. However, DNA yield from forensic samples is frequently limiting. Whole Genome Amplification appears to be a promising tool to obtain sufficient DNA amounts from samples of limited quantity. The WGA method is based upon the “Strand-Displacement Amplification" approach used in rolling circle amplification. The exponential amplification process theoretically enables the amplification of DNA from one single cell up to a million-fold. Therefore the main purpose of our study was to systematically investigate its sensitivity, accuracy and suitability for DNA diluted with quantities of 50, 100, 150, 250 and 500pg. We have performed the study using diluted DNA from two cell lines, HepG2 and K562. The WGA reactions were repeated five times, followed by STR PCR carried out twice for each cell line and dilution. To generate sufficient data, to assess the sensitivity, accuracy and suitability of the Whole Genome Amplification four laboratories were included in this study.
WGA was found to be very efficient, all sample dilutions amplified well, and the amplification yield does not relate to the amount of input DNA. In general ~500ng/µl were obtained, independently of the amount of target DNA. However, reliable STR amplification was dependent on the DNA quantity used for WGA. Consistent and reliable STR typing was only obtained using 500pg genomic DNA. Dropouts and allelic imbalance started to occur at 250pg and more dramatically at 100 and 50pg.
Therefore the usefulness of WGA in forensic casework is limited, however the method may be very useful for saving rare samples provided that the DNA is of adequate quality.


P-021
DNA typing from 15 years old bloodstains

Barbaro A.1, Cormaci P1 and Barbaro A.2

1   Department of Forensic Genetics, 2Director of SIMEF
SIMEF - Reggio Calabria-ITALY
 www.simef.com  - e-mail: simef_dna@tiscali.it


The aim of this study is to compare the efficiency of different validated methods for DNA extraction on old bloodstains. The study has been performed on bloodstains placed on a cotton surface, stored at room temperature for 15 years. As reference were used liquid blood samples,stored at –20°C, belonging to the same donors above. DNA has been extracted from all samples using different procedures (chelex, paramagnetic silica particles, silica membrane column, desalting procedure), then quantified in Real-Time PCR by the Quantifiler Human DNA Quantification kit (Applied Biosystems) and amplified by AmpFlSTR Identifiler kit (Applied Biosystems).
We've evaluated the ability of each method to extract DNA, the quantity of human DNA extracted with each procedure, the ability to perform multiplex STRs amplification and the reproducibility of results obtained .


P-022
Multiplex STRs amplification from hair shaft validation study

Barbaro A.1, Cormaci P1 and Barbaro A.2

1   Department of Forensic Genetics, 2Director of SIMEF
SIMEF - Reggio Calabria-ITALY
 www.simef.com  - e-mail: simef_dna@tiscali.it

Mt-DNA analysis, that is widely used in forensic genetics in case where the amount of DNA is very small or degraded, is unfortunately a complex and time-consuming procedure, so, since several years in other our previous papers, we've showed the possibility to amplify in single-plex DNA extracted from hair shaft. Now in the present study we've evaluated the ability to perform multiplex STRs amplification and the reproducibility of results obtained.
In particular we analysed 20 hair shafts beloging to known donors (2 male and 2 female) using different DNA extraction procedures (fenol-clorophorm, paramagnetic silica particles, silica membrane column,chelex).
Extracted DNA has been quantified by Quantifiler Human DNA Quantification kit (Applied Biosystems) using a 7300 Real-Time PCR System and amplified by AmpFlSTR Identifiler and  AmpFlSTR Y-Filer  kits (Applied Biosystems).
Amplified samples have been analyzed on an ABI PRISM 3130 multicapillary sequencer.
As reference were used saliva samples coming from the same hairs donors.
We verified that in some cases where there's a sufficient quantity and a good quality of medulla cells inside the hair stem a multiplex amplification can be performed and this is very useful for obtaining in a single step the typing of many loci avoiding the loss of DNA.
The ability to identify STRs markers in difficult samples as hair shafts gives a great opportunity to obtain DNA profiles useful for any further comparison or searching in DNA database.
 

P-023
LCN DNA typing from touched objects

Barbaro A.1, Cormaci P1 and Barbaro A.2

1   Department of Forensic Genetics, 2Director of SIMEF
SIMEF - Reggio Calabria-ITALY
 www.simef.com  - e-mail: simef_dna@tiscali.it

A married beautiful woman received to her home, in different slots, 2 envelops containing pornographic photos and indecent proposals from an anonymous persistent admirer.
The woman sent the material above to our laboratory for latent prints development and for searching biological traces for DNA typing.
While latent prints research gave negative results, we were able to found on the stamps some saliva traces useful for DNA analysis. STRs typing showed that both stamps were licked by the same male individual. 
Since the husband of the woman suspected a colleague, after some weeks from the analysis above, he brought us two marking pens (one red and the other one black), that the man was used to utilize at the workplace, for performing DNA typing from any eventual sweat/skin residual found on them, with the aim to compare DNA profiles obtained with the one from stamps.
We were able to obtain from biological traces on the red marking pen a mixed DNA profile, while from the black pen we had a partial DNA profile: all profiles found matched with the one from the stamps.
So DNA analysis confirmed the hypothesis: the husband colleague was the bother perpetrator.
This casework is a further confirmation that it’s possible to type LCN DNA with very good results if an appropriate collection and analysis of biological material is performed.

P-024
X-STRs typing for an identification casework.

Barbaro A.1, Cormaci P1 and Barbaro A.2

1   Department of Forensic Genetics, 2Director of SIMEF
SIMEF - Reggio Calabria-ITALY
 www.simef.com  - e-mail: simef_dna@tiscali.it

X-STRs have been proven to be useful in case of deficiency paternity testing and in effective mother-son kinship and father-daughter testing.  Male individuals inherit their one X-Chr from their mother, while female individuals receive one X from the mother and the other one from the father. So, female individuals fathered by the same man share their paternal Chromosome X.
Hence in case of deficiency paternity in which the mother is available for typing, the possible X alleles of the putative father can be determined and the paternal profile can be reconstructed.
In the present casework we used X-STRs for the identification of a biological material supposed to be belonging to a girl disappeared from several years. In fact in the house of a man (suspected to be the author of another woman murder) was found a headscarf similar to a one obelonging to the girl and inside it some hairs. In absence of any biological sample belonging to the disappeared girl we verified the relationship between hairs above and the mother and the sister of the disappeared girl.
In particular we used Mentype® Argus X-UL that is a new kit commercialized by Biotype for fast and reliable profiling of the following 5 unlinked X chromosomal STRs markers DXS8378, DXS7132, HPRTB, DXS7423 and Amelogenin.
Additionally we investigated in triplex DXS101, DX6789, HumSTRX1 and in duplex GATA1872D05, DX7133 using MWG-Biotech primers and our own amplification protocols.
By comparison between DNA profiles it was possible to identify in the woman, that was surely daughter of the not available father, the paternal possible X alleles and then to verify the presence in the questioned samples of maternal and paternal X-STRs.
The present case demonstrates the impact of additional X-STRs markers in special reverse paternity case that cannot be solved using autosomal markers.


P-025
Study of 16 Y-STRs in the population of Calabria using AmpFlSTR Y-filer kit

Barbaro A.1, Cormaci P1 , Falcone G. and Barbaro A.2

1   Department of Forensic Genetics, 2Director of SIMEF
SIMEF - Reggio Calabria-ITALY
 www.simef.com  - e-mail: simef_dna@tiscali.it


Y-STRs are very useful for forensic laboratories to identify and analyse male DNA from evidence-containing mixtures of male and female DNA (for example in case of sexual assault), in difficult paternity analysis or for reconstruction of male lineage or application in kinship analysis.
AmpFLSTR® Yfiler™ PCR Amplification kit is the last commercial kit for Y-STRs analysis produced by Applied Biosystems. It uses the 5-dyes chemistry for co-amplification, in a single PCR reaction, of 16 Y-chromosome STRs (DYS456, DYS389I, DYS390, DYS389II, DYS458 DYS19 DYS385 DYS393 DYS391 DYS439 DYS635 DYS392 YGATAH4 DYS437 DYS438 DYS635 DYS448), including the European Minimal Haplotype loci, the loci recommended by the Scientific Working Group on DNA Analysis Methods (SWGDAM) and 6 additional highly polymorphic loci.
In the present study we analysed the distribution of the Y-STRs above in 3 populations from a Southern Italy region: Calabria.
In particular DNA was extracted, by Instant Gene Matrix (Biorad) treatment, from blood/saliva samples of male unrelated healthy donors (100 per each area), since 3 generations, at least, belonging to the populations of Reggio Calabria, Catanzaro and Cosenza.
All samples were quantified by the Quantifiler™ Human DNA Quantification Kit using  a 7300 Real Time System and then amplified according to the Yfiler™ kit protocol using GeneAmp PCR Systems 9600,9700,2400,2720 thermal cyclers (Applied Biosystems). Female and Male Positive controls and negative controls were used during all amplification steps.
Amplified products were analyzed by capillary electrophoresis on ABI PRISM 310 and ABI PRISM 3130 Genetic Analyzers (Applied Biosystems) employing Genotyper and GeneMapper 3.2 softwares.


P-026
Male contribution in the constitution of the Brazilian Centro-Oeste populations estimated by Y-chromosome binary markers

Barcelos RSS1,2,3, Ribeiro GGBL1, Silva Jr. WA4, Abe-Sandes K4,5, Godinho NMO1,2, Marinho-Neto F7, Gigonzac MAD7, Klautau-Guimarães MN1, Oliveira SF1.
1Departamento de Genética e Morfologia, Universidade de Brasília, Distrito Federal, Brazil; 2Superintendência de Criminalística, Secretaria de Segurança Pública do Estado de Goiás, Brazil; 3Departamento de Biomedicina, Universidade Católica de Goiás, Brazil; 4 Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brazil; 5Departamento de Ciências da Vida, Universidade do Estado da Bahia, Campus I - Salvador, Bahia, Brazil.

Due to Brazil’s large dimension, this country is divided in five geo-political regions: South, Southeast, Center-West, North and Northeast. The Center-West region is the subject of our study and is composed by three states - Goiás, Mato Grosso and Mato Grosso do Sul - and the Federal District. The settlement of this territory, which was a result of the miscegenation among different ethnic groups, especially Europeans, Africans and Amerindians, did not happen in a homogeneous way, which reflects in the current genetic population composition. Meanwhile the Brazilian colonization was initiated in XVI century, the Center-West region settlement took place only after XVII century and the Federal District, where is placed the Federal capital (Brasília), was founded in the late 1950s. Differently from the others Brazilian’s regions, the colonization of Center-West region was derived from internal migrations of already mixed individuals from all others Brazilian regions. Another Brazilian peculiarity is the directional mating between European males and Amerindian or African females. Therefore, after consider these characteristics, could this region be considered as the best representative population group of the Brazilian population? How is the male constitution in the Brazilian Center-West? Seeking answer these questions, we studied eleven unique-event polymorphism (UEPs), located in the non-recombinant region of the Y chromosome, in 200 unrelated men from Goiás state and Federal District. The results showed that the last population presented a greater genetic diversity than the first one, which reflects in a low divergence between these two populations. The greater genetic diversity of Federal District corroborated the historic data of migrations from all regions of the country and indicated this population as the most representative group of the Brazilian population genetic constitution. The most common haplogroup in this survey, P92R7, presents a wide geographic distribution. However, due to Brazilian settlement history, its presence may reflect a European contribution. The contribution estimated using European haplogroups was similar in both population and is greater than the African one. It was also observed a little male contribution from Amerindian to the constitution of both populations and from Japanese only to Federal District constitution. These results demonstrated a greater male contribution of Europeans than Africans or Amerindians to the formation of both populations, which corroborated the historic data of this region settlement.

contact: silviene@unb.br

Tidak ada komentar:

Posting Komentar