The use of saliva samples is an alternative to blood samples when a la
rge number of control samples are to be compared by DNA investigations
. The most convenient and safe method is by using cotton wool swabs. I
n this investigation the average DNA content of saliva samples taken b
y three different sampling techniques (i. e. cotton wool swab, filter
paper, liquid saliva) was compared. In addition the possibility of a D
NA mixture of saliva samples after intensive kissing was investigated
by taking samples from voluntary pairs. Mixed STR patterns were found
in five samples but restricted to the first sampling after kissing wit
hin max. 60 s.