A brain from the remaining half of a University of Texas collection of brains. The school recently confirmed that the 100 "missing brains" have been destroyed.Adam VoorhesThe 100 missing brains were part of an initial collection of 200 that had been preserved in formaldehyde and kept at  the university's Animal Resources Center in Austin. Most of the specimens had come from a state mental institution and were given to the school 30 years ago. The brain of former Marine Charles Whitman, who went on a shooting rampage from a UT tower and killed 16 people in 1966, was said to be among the brains in the collection.

However, half of that collection had been missing from the Animal Resources Center since the 1990s, a story that only appeared in the mainstream media after a book on the mystery, "Malformed: Forgotten Brains of the Texas State Mental Hospital,” by Adam Voorhes and Alex Hannaford came out this week.

That media attention prompted an investigation by the university into the disappearance of the specimens.

Despite an initial report by the Los Angeles Times in which a UT professor said he'd heard that the brains had been discovered safe at the school's San Antonio campus, the school confirmed late Dec. 3 that that report was untrue.

The university made the following statement about the 2002 disposal of the brains:

This was done in coordination with faculty members who determined that the specimens had been in poor condition when the university received them in the 1980s and were not suitable for research or teaching. Faculty members then maintained possession of other brain specimens in the collection that the university continues to own.

This occurred prior to the renovation of the Animal Resources Center, where the specimens had been stored in a secure location. We believe the workers disposed of between 40 and 60 jars, some of which contained multiple human brains, and worked with a biological waste contractor to do so safely.

We have no evidence that any brain specimens were shared with other universities or health institutions, though we will continue to investigate those reports.

We have no evidence at this time that any of the brain specimens came from Charles Whitman, though we will continue to investigate those reports.

The university will also investigate how the decision was made to dispose of some of these specimens and how all brain specimens have been handled since the university received its collection from the Austin State Hospital in the 1980s.

University officials will appoint a broader investigative committee to examine these issues. As researchers and teachers, we understand the potential scientific value of all of our holdings and take our roles as stewards of them very seriously.

- With files from Bloomberg and the Los Angeles Times