Background: We describe a simple, non-invasive mouthwash sampling method fo
r rapid DNA isolation to detect cytokine gene polymorphisms. In the present
paper, interleukin-1 beta (IL-1B) and interleukin-1 receptor antagonist (I
L-1RN) gene polymorphisms were studied.
Methods: Two mouthwash samples and blood samples were collected from 11 hea
lthy individuals. The second mouthwash sample was stored for 7 days at room
temperature. Polymerase chain reaction amplification was used to identify
a bi-allelic polymorphism at position +3953 in the IL-1B gene and a variabl
e number of tandem repeats (VNTR) polymorphism in the IL-1RN gene.
Results: Our results show that the typing of these cytokine gene polymorphi
sms using DNA isolated from mouthwash samples did not differ from those obt
ained by a phenol/chloroform isolation method from EDTA anti-coagulated blo
od. Moreover, reliable results from mouthwash samples were obtained after s
torage for at least 7 days at room temperature.
Conclusions: Mouthwash can be the method of choice to study gene polymorphi
sms in periodontitis and other chronic inflammatory diseases.