DNA testing for Sydney gang rape accused

Three teenage boys accused of gang raping a girl will be forced to undergo DNA testing, despite one of them objecting to the test as an "invasion of his physical integrity".

The youths allegedly drugged and sexually assaulted the 15-year-old girl at one of the boys' homes in Mt Druitt, in Sydney's west, on May 21.

In the Parramatta Children's Court on Wednesday a magistrate rejected a 17-year-old's complaint via his lawyer that testing of his pubic area would be "in effect, some invasion of his physical integrity" and ordered the test be done within seven days.

Police prosecutor Kelly Chessor told the court the alleged incident was "an extremely serious aggravated sexual assault commonly referred to as gang rape" and involved "excessive brute force to the victim's vagina".

"The community have expectations that these matters are investigated to finality," Ms Chessor said.

The victim knew only one of the boys and later could only describe the others by their first name or ethnicity, the court heard.

As part of police investigations, detectives intercepted the teenagers' mobile phones and interviewed the 17-year-old's girlfriend who confirmed that he was at the house in question at the time of the alleged offence.

The boys have been in custody since July and will remain so until their next court appearance on October 28.