Male DNA test yields clues in TX criminal cases

HOUSTON Experts say the Y-chromosome detection analysis is able to extend the evidence collection time from 48 hours on up to 120 hours. It separates male DNA profiles from those belonging to females and hones in on saliva, skin cells, semen or other biological evidence.

The University of North Texas Center for Human Identification in Fort Worth has been refining the testing kits.

The Texas Department of Public Safety crime lab in mid-2009 started doing its own male-specific DNA tests.

The Harris County Medical Examiner's Office biology lab also is using the test. Since June, it has obtained positive results in 20 sexual assault cases. None has gone to trial yet.