DNA profiling is not infallible and can lead to innocent people being wrongly convicted of serious crimes, scientists have warned.

The popularity of TV crime dramas such as The Killing, as well as real-life breakthroughs such as the case of Karlie Pearce-Stevenson and her daughter Khandalyce, can lead to unrealistic expectations of the crime-solving ability of forensic science.

Killed: Karlie Pearce-Stevenson and Khandalyce Pearce. Credit:NSW Police

Forensic DNA specialists were instrumental in confirming the breakthrough in one of NSW's baffling unsolved crimes: matching the remains of an unidentified young woman found in Belanglo State Forest with the bones of a toddler found years later in South Australia.

And a smear located on a garage flood was used by prosecutors to link Robert Xie to the Lin family murders.