Gene Hackman and Wife Betsy's Full Final Autopsies Will Take Weeks

It'll be a while before we get the full story on Gene Hackman, his wife Betsy, and their dog’s suspicious deaths -- 'cause TMZ has learned that even with the initial autopsy, the final report will take a few more weeks.

Sources tell TMZ that after the autopsy is done by the New Mexico Office of the Medical Investigator, it’ll take 4 to 6 weeks for toxicology and other tests to come through before the final report is issued.

Authorities have been super puzzled over their deaths -- making a note of how Gene's front door to his NM property was open when they entered for the search warrant of their house.

They noted how Betsy was found in the bathroom along with a space heater and pills -- and it looked like she had been dead for a while. Her body was in a state of decomposition, with facial bloating and mummification in her hands and feet.

What's more, the heater was right next to her corpse, and the pills were scattered nearby. Police say Gene was found in a separate room.

The deceased German Shepherd was found 10 to 15 feet from Betsy, while two other dogs were found alive and healthy -- one inside the house and the other outside.

The fire department checked the scene and said they didn’t find any signs of a carbon monoxide leak or poisoning.