Typeability of AmpFlSTR SGM Plus loci in brain and thyroid gland tissue samples incubated in different environments

Autolysis and putrefaction are crucial factors responsible for degradation of cells, tissues, and organs. Postmortem changes may assume different course depending on extrinsic and intrinsic conditions. The aim of the study was assessment of environmental effect on typeability of AmpFlSTR SGM Plus loci: D3S1358, VWA, D16S539, D2S1338, D81179, D21S11, D18S51, D19S433, TH01, FGA, and gender marker amelogenin. Brain and thyroid gland tissue specimens collected during autopsies of five persons aged 20-30 years were incubated at 21 degrees C and 4 degrees C in different environmental conditions. DNA was extracted by organic method from tissue samples collected in 7-day intervals and subsequently typed using AmpFlSTR SGM Plus kit and ABI 310. A fast decrease in typeability rate was seen in specimens incubated in peat soil and in sand. Brain tissue samples were typeable in all AmpFlSTR SGM Plus loci within 126 days of incubation at 4 degrees C. Faster DNA degradation was recorded in thyroid gland specimens. In samples with negative genotyping results, no DNA was found by fluorometric quantitiation.     

A search for obligatory paternal alleles in a DNA database to find an alleged rapist in a fatherless paternity case

Abstract: A sexual assault case resulted in a pregnancy, which was subsequently aborted. The alleged father of the fetus was unknown. Maternal and fetal types were obtained using the 11‐locus AmpF?STR^® SGM Plus^® kit. The national DNA database was searched for the paternal obligatory alleles and detected two suspects who could not be excluded as father of the male fetus. Additional typing using the AmpF?STR^® Minifiler^? kit, containing three additional autosomal loci, was not sufficient to exclude either suspect. Subsequent typing using the PowerPlex^® 16, containing four additional loci, and Y‐Filer^? kits resulted in excluding one suspect. Searching a database for paternal obligatory alleles can be fruitful, but is fraught with possible false positive results so that finding a match must be taken as only preliminary evidence.     

Buying stolen goods: the ambiguity in trading consumer-to-consumer

This study investigates the buying of stolen goods in Denmark. The study consists of a self-report survey based on a representative sample of the general Danish population (n = 2311) and six focus group interviews consisting of both informants experienced with buying stolen goods and of those with no experience (n = 37). The survey showed that 4.8% had bought stolen goods, while 15.7% were uncertain whether they had bought stolen goods. Young people, males, and unemployed were more likely to purchase stolen goods. No clear correlation between income and buying stolen goods was found. Focus groups suggest the buyers of stolen goods did not buy stolen goods because they could not afford legitimate products. We recommend targeting consumers not interested in buying stolen goods with information about how to avoid such activity.     

DNA Analysis and Document Examination: The Impact of Each Technique on Respective Analyses

Threatening letters, counterfeit documents, and anonymous notes can commonly be encountered in criminal situations. Such handwritten documents may encourage DNA to transfer from the writer's hands and lower arms when these areas come into contact with the document. As any DNA transferred is likely to be at a low level, sensitive low copy number (LCN) DNA analysis can be employed for testing document exhibits. In this study, we determine locations on the document that are most commonly touched during writing and handling and compare DNA recovery from these sites. We describe the impact of DNA sampling on subsequent document examination techniques including the ESDA^® and likewise the effect of the ESDA^® and two other document examination techniques on subsequent DNA analysis. The findings from this study suggest that DNA results can be obtained through targeted sampling of document evidence, but that care is required when ordering these examination strategies.     

The Use of Adhesive Tape for Recovery of DNA from Crime Scene Items

Abstract: The selection of the appropriate method of collection of biological material from crime scene items can be crucial to obtaining a DNA profile. The three techniques commonly used for sampling items are: cutting, swabbing, and taping. The tape sampling technique offers an advantage, in that it enables the collection of a potentially highly informative source of DNA, shed epithelial cells, from selected areas on crime scene items (the inside fingers of a glove, for instance). Furthermore, surface collection of biological material by taping reduces co‐sampling of known PCR inhibitors such as clothing dyes. The correct choice of tape for crime scene item sampling is important. Not all tapes are suitable for biological trace evidence collection as well as DNA extraction. We report on one tape that met both these criteria. Three different cases are presented which demonstrate the usefulness of adhesive tape sampling of crime items. Finally, the advantages of the tape collection technique are discussed and guidelines for preferred areas of tape sampling on various casework items are presented.