Stray Y chromosomes can confirm an allegation of rape.(Brief Article)

2002 APR 11 - (NewsRx.com & NewsRx.net) -- A test that can prove a woman has been raped even if no sperm are found should be widely adopted, a large-scale study suggests.

After the trauma of rape, women who report it have to undergo a medical examination to look for sperm. But the test can fail, and as a result the woman's claim to have been raped may not be believed. Now a French study has confirmed that a backup test can often detect the male Y chromosome even if no sperm are found.

The standard test, in which technicians use microscopes to look for sperm in vaginal, oral or anal swabs, is very sensitive. But it can fail if the swabs are taken more than two days after the rape, if the assailant has a low sperm count or doesn't ejaculate, or if the woman is menstruating or using spermicide. It can also fail if the rape involved oral or anal sex, because salivary and bacterial enzymes can rapidly destroy sperm.

But an attack by a man will usually leave traces of skin cells, which will carry the telltale Y chromosome. These chromosomes can be detected even if there's only one male cell for every 5000 female cells.

Philippe de Mazancourt, a forensic biologist at the Raymond PoincarZ Hospital in Garches, France, and his colleagues used this test to examine 79 women who said they had been raped. The researchers found fragments of Y chromosome in nearly 30% of the cases for ...