Online reference database of European Y-chromosomal short tandem repeat (STR) haplotypes.

The reference database of highly informative Y-chromosomal short tandem repeat (STR) haplotypes (YHRD), available online at http://ystr.charite.de, represents the largest collection of male-specific genetic profiles currently available for European populations. By September 2000, YHRD contained 4688 9-locus (so-called "minimal") haplotypes, 40% of which have been extended further to include two additional loci. Establishment of YHRD has been facilitated by the joint efforts of 31 forensic and anthropological institutions. All contributing laboratories have agreed to standardize their Y-STR haplotyping protocols and to participate in a quality assurance exercise prior to the inclusion of any data. In view of its collaborative character, and in order to put YHRD to its intended use, viz. the support of forensic caseworkers in their routine decision-making process, the database has been made publicly available via the Internet in February 2000. Online searches for complete or partial Y-STR haplotypes from evidentiary or non-probative material can be performed on a non-commercial basis, and yield observed haplotype counts as well as extrapolated population frequency estimates. In addition, the YHRD website provides information about the quality control test, genotyping protocols, haplotype formats and informativity, population genetic analysis, literature references, and a list of contact addresses of the contributing laboratories.

Application of a Y-STR-pentaplex PCR (DYS19, DYS389I and II, DYS390 and DYS393) to sexual assault cases.

A survey of 89 random rape cases including 166 semen traces, according to the prostate-specific-antigen test, showed the need for a more efficient method of DNA-profiling. No male autosomal STR-profile could be detected, after differential lysis, in 35% of the 84 samples usually containing high amounts of the victim's cells, i.e. vaginal/anal washings and knickers. A Y-STR-pentaplex was applied to the stored sperm fraction of 50 unsolved semen traces, with success in 48% of them. The chance of success depends of the amount of total DNA available and of the quality of the extracted DNA.