Maciej Jędrzejczyk

Genetic investigation of biological materials from patients after stem cell transplantation based on autosomal as well as Y-chromosomal markers

The authors presented the results of DNA polymorphism investigation of blood, buccal swabs and hair follicles originating from patients after allogeneic hematopoietic stem cell transplantation. The real-time and multiplex assays based on polymerase chain reaction within the range of autosomal as well as Y-chromosomal markers were applied to assess the possible dangers arising from investigation of these materials in forensic genetics. The results revealed that not only post-transplant blood and buccal swab, but also recipient hair, up to now regarded as devoid of any donor’s cells, do not constitute entirely safe material for forensic purposes. Their analysis can lead to the false identification of gender or male haplotype. The investigation of sex-determining region Y and Y-chromosome short tandem repeats performed in female recipients with male donors resulted in the designation of donor’s DNA in hair cells as well as in blood and buccal swabs. Therefore, biological stains gathered from crime scenes should not be analysed exclusively based on the investigation of male-specific markers.

Population database on 15 autosomal STR loci in 1000 unrelated individuals from the Lodz region of Poland

Allele frequency data and forensic efficiency parameters for 15 STR loci: D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA, were estimated from the sample of 1000 unrelated individuals from the Lodz region of Poland. The combined MP and PE for all 15 loci are 4.8 x 10(-18) and 0.9999989, respectively. The comparison of our data with other Polish populations revealed statistically significant differences in 6 out of 15 loci between Lodz and the Podlasie region of Poland.

Forensic evaluation of the AmpFlSTR® NGM™ loci in Lodz region of Poland population sample

The paper is focused on population data for 15 polymorphic STR loci included in the NGMTM amplification kit, obtained from a sample of 800 individuals from the Lodz region of Poland. Main statistical parameters of forensic interest were calculated and Hardy–Weinberg equilibrium was verified for each locus. Departure from HWE was not significant after applying Bonferroni corrected significance level for multiple testing (p = 0.0033). Comparative analysis between chosen populations was performed and some significant differences were found among investigated populations. Obtained values of parameters for NGM™ multiplex amplification kit point to wide range of possible applications of investigated STR markers to forensic genetics.

Polymorphism of 12 STR loci included in the Investigator HD-plex kit in Polish population of Lodz region.

In this study Polish population data as well as efficiency parameters of 12 STR loci included in the Investigator HDplex set were presented. This set contains 9 systems not available in any other commercial multiplexes, ie.: D2S1360, D3S1744, D4S2366, D5S2500, D6S474, D7S1517, D8S1132, D10S2325 and D21S2055. The evaluation was preformed based on DNA samples derived from 303 unrelated individuals living in Lodz region, central part of Poland. The obtained distribution of the genotypes is consistent with the assumptions of the Hardy and Weinberg equilibrium (HWE). It reflects properly genetic structure of the studied population compared with other populations of Europe and the world. It indicates the linkage equilibrium within the pairs of investigated loci, as well as with regard to other syntenic loci. The total value of the power of exclusion (PE) and the random match probability (MP) were respectively 0.99999988 and 5.2 × 10-18. Therefore the polymorphism of examined genetic markers within the Investigator HD-plex multiplex allows for a significant increase of the evidence value. Thus it constitutes an excellent tool for resolving difficult cases in the field of forensic genetics.