Gm(5) Grouping of Dried Bloodstains

Abstract

An absorption—inhibition method for the detection of Gm(5) in dried bloodstains is described. This antigen compares very well with other blood group systems with regards to the amount of bloodstain required and its resistance to degradation.

Particular reference is made to the association of Gm(5) with Gm(-1, −2). When a stain fails to inhibit anti-Gm(1) and anti-Gm(2), this may represent a true Gm(-1, −2) result, or that there was insufficient material to inhibit each antiserum. The detection of Gm(5) in a bloodstain extract provides an objective means of confirming the apparent absence of Gra(1) and Gm(2) as representing a true Gm(-1, −2) result.