Identification of blood stains by non-genetic characteristics: The HBs antigen of viral hepatitis B

In forensic cases, until recently, identification of biological stains was based on the use of genetic markers, such as blood groups.

In this paper, we show that another acquired characteristic, even if not immutable during life, may afford similar possibilities.

As an example, we have demonstrated that the HB_s antigen, associated with the hepatitis B virus, can help in the identification of bloodstains.

The requisite condition for using this new marker, is that not too much time should elapse between the time the biological stains are formed and the moment when victim and suspected individual are examined for comparison of their blood with the stain.

We have shown that in a dried state, the HB_s antigen is very stable for at least six months. In vivo, it persists for a few week to 6 or 7 years according to the case.

HB_s antigen is a relatively rare factor, its frequency being 0.5% in the Belgian population; the frequency reaches 2 to 3% in the Mediterranean population who constitute most of the immigrants in Belgium.