When kissing, DNA from the couple also swapped with the fluid from the lips

illustration (Photo: Thinkstock)

Kissing is an expression of affection between pair of lovers to strengthen the emotional bond. Overview This activity looks rather disgusting. When kissing, exchanging fluid from lip to lip. Not only liquids, but also DNA are swapped.

The researchers in Comenius University in Slovakia conducted research on 12 couples lovers. All are requested kissing for approximately 2 minutes. After that, samples of saliva on lips women couples immediately taken with pause 5, 10, 30 and 60 minutes. Samples before the couple kissing also collected.

Because the methods used in the research is only based on the detection of the Y chromosome, then the researchers can only identify DNA from men only. Researchers explained that DNA the male couples is still lagging in the saliva his couple and can be identified up to 1 hour later.

"We were able to determine the presence of male DNA in the saliva of women, even after 60 minutes with a simple qPCR test. Other than that, more than a third our sample may be could obtain genotype Y within 10 minutes after kissing a man," said the researcher, as reported by Natalia Kamodyova Medical Daily, Tuesday (29/01/2013).

Although the study was conducted on volunteers, Kamodyova explained that the same mechanism could also apply in different case, for example on cases of rapes, where the perpetrator the man, coerce kiss the victim. DNA is left behind on saliva can be used as evidence for ensnare perpetrator.

"Our data with clearly show the possibility of using saliva as evidence of sexual harassment, adultery, rapes or other sexual attacks, provided that the biological samples can be collected in a short time after the incident," said Kamodyova.

Unfortunately, Kamodyova and his team did not researching whether the DNA is left behind it could survive more than 1 hour. The research published the journal Forensic Science International this is also not explain whether the same way can be done on the victims who has been died.

Source:  Medical Daily