California investigators kept DNA from 3 violent crime scenes for decades. A suspect was just arrested in Georgia

Mark Manteuffel was linked by DNA to three cold cases, authorities said.

(CNN)For more than two decades, all California authorities knew about the man behind three violent sex crimes was his DNA profile.

Two women in Sacramento had been attacked in the early 1990s inside their homes. A third, a 22-year-old student in Davis, had been shocked with a stun gun and assaulted while on a jog.
The name and face of who attacked them remained a mystery for years. Then last week came a major development: the arrest in Decatur, Georgia, of a 59-year-old retired correctional institution administrator.
The apprehension of Mark Jeffery Manteuffel, law enforcement officials said, owed directly to three key factors: the persistence of one dogged detective, the use of a groundbreaking legal maneuver to keep the cases alive and critical scientific advances that helped authorities match the little information they had about the suspect -- his genetic code -- with his relatives' to figure out his identify.
    "This case represents so much: the dedication of law enforcement, the critical importance of keeping rape kits and testing those kits no matter how long ago those crimes occurred, the need for passion and persistence, and a desire to pioneer our law enforcement tools so that violent criminals can be identified and brought to justice," Sacramento County District Attorney Anne Marie Schubert said during a Monday news conference.
    The cases in which Manteuffel stands accused represent the latest in a series of recent breaks made in long-dormant criminal probes thanks to the growing availability of DNA. Using popular online ancestry-tracing projects, authorities compare genetic material left at crime scenes to known relatives' genetic data and often can draw a line directly to a suspect.
    "A little over a year ago came this concept of investigative genetic genealogy -- the latest and perhaps the greatest advancement to help law enforcement find the truth and solve violent crime," said Schubert.
    The FBI in Atlanta did not respond to CNN's request for comment.
    Manteuffel was arraigned Friday in Sacramento but did not enter a plea. He has been charged with seven counts, including torture, rape and inflicting great bodily injury by using a knife, court records show.
    He is being held without bail.

    He waited inside their homes

    The crimes, when they unfolded, shook their communities in and around California's state capital.
    Around 8:30 p.m. on May 5, 1992, a 52-year-old woman walked into her home, deactivated her alarm and "was almost immediately accosted and assaulted by someone who was lying in wait inside of her residence," Sacramento County Sheriff Scott Jones said Monday in recounting the crime.
    "For the next over three hours, she was assaulted, sexually assaulted and various sexual acts were committed against her until ultimately the suspect fled the residence," Jones said. The suspect's DNA was found at the scene.
    Less than two years later, a young college student went for an evening jog, planning to grab some dinner at a local market.
    "As she jogged through a well-known, safe neighborhood in Davis, California, she was approached and grabbed by a masked man,