CLEVELAND -- DNA results confirm that Ariel Castro is the father of the six-year-old little girl who has likely lived her entire life under his watch.
"It's a very powerful tool for helping to solve crime," said DNA Technical Leader Lewis Maddox, with the Ohio Bureau of Criminal Investigation.
"DNA is basically the blueprint which makes us who we are. Each person gets 50 percent of their DNA from their mother and 50 percent of their DNA from their father," said Maddox.
In a fast-track request, researchers mapped Castro and his four victims overnight, linking him to the daughter of Amanda Berry.
There are no Ohio cold cases linked to Castro, and a national search is still underway, expected to be complete next week.
"Typically for a paternity case we will have submitted in, a swab from the cheek of the child, a swab from the mother, and a swab from the alleged father," said Maddox.
Investigators are now comparing Castro's profile against almost 12 million profiles nationwide in the FBI's Combined DNA Index System, known as CODIS.
Only 400,000 of those profiles are for people. The rest are for items marked with a unique makeup.
"It can be found in blood. It can be found in semen, saliva. DNA is also usefully in identifying unidentified remains, such as bones that are found that are quite old," he said.
To date, Cleveland Police and the Cuyahoga County Medical Examiner confirm there have been no remains found at the Seymour Avenue house where the women were jailed for a decade.
If found, that evidence could be tested to attempt to link Castro to a series of alleged forced miscarriages.
"As long as the samples are preserved, reasonably well, we're able to test those samples," said Maddox.
An experienced obstetrician told Channel 3 News, depending upon how far along a woman is in a pregnancy, there could be very little evidence left from a previous miscarriage.
To prove aggravated murder charges, as Cuyahoga County Prosecutor Tim McGinty mentioned, lawyers say prosecutors would need to show that Ariel Castro actually caused the early end to a pregnancy.
Years after the fact, that could be quite a challenge.