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The extended possibilities of forensic stain analyses during recent years have mainly resulted from the application of DNA technology. Among the VNTR polymorphisms, one can differentiate between five consecutive generations of systems, i.e. multi locus systems (MLS), single locus systems (SLS), so-called AMPFLP's (amplificable fragment length polymorphisms), short tandem repeats (STR's), micro satellite systems. The routine application in our laboratory lets us distinguish 3 phases: (I) RFLP phase (MLS+SLS); (II) combined application of RFLP-SLS and AMPFLP's; (III) PCR phase (combined application of AMPFLP's and STR's.--Investigations applying conventional blood group systems and RFLP analysis have been cancelled in phase III. Since 1989 328 cases have been investigated. The number of cases per year was doubled in phase III compared to phase I, but the proportion of DNA determination has been increased by app. 800%. Although in phase III the stain material was on average more degraded and quantitatively smaller the application of STR systems was successful in 90% of all cases and therefore much more effective than other systems. Compared to phase I, the probabilities of inclusion were smaller in phase III. Problematic stains were more often investigated. Also, a strategic change has occurred. New standards had to be elaborated, i.e. to the avoidance of contamination, to the critical evaluation of stain composition and to the validation of systems.

The identification of seminal traces is exceptionally difficult, if the semen of the assailant is azoospermic. The evident value of prostatic acid phosphatase (PAP) activity must be evaluated in such cases with caution. In a murder investigation of a 13 year old girl a positive PAP reaction was found in vaginal swabs and in her underpants. Spermatozoa could not be found. Using the gas-chromatographic method, described by Douse (1985) the presence of prostaglandin E could be demonstrated in the swabs as well as in the crotch of the underpants. The offender was found to be a man with azoospermia, who admitted intercourse but with the consent of the victim. The E prostaglandins are mainly synthesized in the vesiculae seminal and seen to be specific for semen. Swabs taken from mouth and rectum showed negative reactions for prostaglandins in this case. Prostaglandins could never be detected in vaginal swabs taken at least 7 days after intercourse. Conversely Douse could detect prostaglandins in swabs up to 58 hours after intercourse. Apparently the prostaglandin detection by Douse provides a suitable alternative besides to the quantitative and immunological PAP detection or the immunological detection of the protein p 30.

The single locus probes MS 1, MS 8, MS 31 and MS 43 were investigated in combination with the restriction enzyme HINF I. The frequency distribution of fragment sizes detected by the polymorphic probe MS 8 was plotted for individuals from the Münster area and compared with an English survey. Clear discrepancies were found. The heterozygosity for the four systems was calculated and compared to the English figures. Only MS 8 showed a significant difference.

A sample of 73 families which had been investigated by conventional paternity grouping was in addition subjected to DNA analysis using the multi locus systems 33.15 and 33.6. A comparison with the results of a conventional expert's opinion shows complete accordance. In cases showing exclusions in the conventional systems there were also exclusions by the multi locus systems and in cases without exclusions in the conventional systems no exclusions were found using multi locus probes. New mutations were not observed. In stain cases the resulting band patterns were often partially deficient. The problems in assigning such patterns with those observed in fresh samples are discussed.

The identification of ABH antigens from compact bone tissue is known from many sources. The purpose of this study was to make a contribution to the localization of blood-group-active substances in compact bone tissue. A variety of preparation and identification methods were successfully used and compared. Samples were extracted from compact bone tissue, separated by HPTLC, and examined using the absorption-elution and PAP techniques. Additionally, the PAP technique was carried out on cryostat sections. Serologically active blood-group substances were consistently demonstrated in the organic components of the haversian canals.

The DNA-fragment (St 14.1) from the human X-chromosome recognizes a series of approximately 10 alleles after Taq I digestion. The presence of constant bands simplifies the assignment of the alleles to a definite Kb-size when small differences exist between the alleles. 348 individuals were investigated and included 120 mother/child combinations. The verification of the Hardy-Weinberg equilibrium gave a value of 32 in the chi square test by 20 degrees of freedom and therefore a P-value of 95-97.5. The allele frequencies range from 1%-40% with an expected exclusion rate of 77.3% (for mother/daughter combinations).

The occurrence of unusual band patterns in the protein systems Gc, F XIII B and PLG is described. During the routine investigation of these systems in paternity, identity and criminal cases, several examples of alterations or additions to the normal band patterns have been observed. This was particularly noticeable in post mortem samples, stored liquid blood samples and blood stains. A connection between alterations in the form due to charge changes and changes to the isoelectric point from ageing of blood samples is demonstrated.

Stroma from hemolyzed erythrocytes of blood groups 0, A1, B and A1B were obtained and subjected to butanol/phosphate buffer extraction. This extract was separated using HPTLC, and the ABH and Le substances were detected on the chromatogram using the PAP technique. The staining of the bands allowed specific demonstration of the serologically active glycosphingolipids present in the ABH and Le blood group substances. The antigens of the AB0 system showed a 3- to 12-band pattern. Each of the antigens Lea and Leb presented 3 bands. The slight differences in the levels of glycosphingolipids of equal chain lengths are probably due to differences in their chemical structures.

Membrane structures (stroma) were obtained from erythrocytes of various ABO and Le blood groups using a butanol/phosphate buffer extraction. The extracts were separated using thin layer chromatography and the ABO and Le antigens demonstrated directly on the chromatogram using the PAP-technique. Detection was carried out using either Ulex europaeus lectin or monoclonal antibodies. By this method the direct staining of the bands allowed a specific demonstration of the ABH and Leactive glycosphingolipids. A determination of the number of sugar residues is possible as well as the recognition of quantitative variants.