OMAHA, Neb. (AP) — An expert has testified that DNA recovered from the scene of a home break-in could not rule out a former doctor on trial in the deaths of four people with ties to an Omaha medical school.

A judge sustained a defense objection Tuesday to the expert’s testimony that the DNA likely came from Anthony Garcia or a male related to him.

The DNA was collected from the Omaha home of Dr. Chhanda Bewtra, where a break-in occurred in May 2013 around the same time her Creighton University School of Medicine colleague, Dr. Roger Brumback, and his wife, Mary, were killed.

Prosecutors say Garcia also killed the 11-year-old son of Creighton’s Dr. William Hunter, and the family’s housekeeper in 2008. They say Garcia was angry at being fired by the doctors in 2001.