Conducting DNA analysis

To establish a DNA profile a buccal (cheek) swab is generally recommended. For the DNA profile of trace samples, samples of different materials are taken from the relevant objects.

The procedure in DNA analysis for use in criminal proceedings is as follows:

• The investigating police or legal authorities deliver a DNA sample collected in the search for evidence or with a buccal swab to a federally designated DNA analysis laboratory to establish a DNA profile.
• The DNA coordination point at the Zurich Institut for Forensic Medicine stores new profiles in the CODIS database and compares them with reference profiles.
• If a profile matches with one of the reference profiles, the AFIS DNA Services link the anonymized data with the appropriate personal and case data and send a report to the investigating police or judicial authority
• Data is exchanged via a specially created secure data transfer platform, monitored by the AFIS DNA Services.

To prevent mismatches in the DNA profiling of traces and samples acquired through a buccal swab, laboratories rely on an independent second analysis.