Genetic traces from envelopes that contained the serial killer’s apocalyptic and police-taunting letters in the 1960s appear to have cleared a schoolteacher and child molester whom Vallejo, Calif., police and others once identified as the Zodiac, said inspectors Kelly Carroll and Michael Maloney.

"Arthur Leigh Allen does not match the partial DNA fingerprint developed from bona fide Zodiac letters," Carroll said.

Allen was named by Vallejo Police Capt. Roy Conway as his department’s Zodiac suspect after Allen’s death at age 58 in 1992.

Maloney and Carroll, who took over the cold case investigation in 2000, also said they recently discovered additional evidence in the Zodiac case that could soon allow them to create a full DNA profile of the Zodiac, who killed five Bay Area residents in 1968 and 1969.

The killer sent coded letters announcing his crimes.

The Zodiac sent 21 letters about his crimes to Bay Area newspapers in the late 1960s. Each was signed with a cross within a circle. His crimes and cryptograms baffled police and fascinated amateur detectives for three decades. Books have been written and Web sites are maintained — all with theories about who the killer might have been.

The serial killer’s known crimes began with the fatal shooting of two Vallejo teenagers on their first date. He then killed two other people, one in Vallejo and another in Napa County, before his final homicide, an execution-style slaying of a San Francisco cab driver in October 1969.

"When I die, I will be reborn in paradice (sic) and the (word missing) I have killed will become my slaves," one of his coded letters said.

Several envelopes in which those letters were sent allowed the San Francisco police DNA lab headed by Dr. Cydne Holt to reach its new conclusions.

Although they had been analyzed for handwriting and traditional fingerprints, DNA analysis, Carroll pointed out, "was science fiction back in 1969."

An effort was made to DNA-test the letters six years ago, with inconclusive results. But new technology has been developed since.

Holt retrieved saliva traces beneath a stamp and was able to replicate a DNA sample large enough to test. That sample was compared with brain tissue recovered from the 1992 autopsy of Allen, who was identified as the elusive killer in two books by Robert Graysmith, the most recent of which, "Zodiac Unmasked," was published this year.

Vallejo police had originally zeroed in on Allen, a former teacher, after the first two Zodiac killings when an acquaintance told officers that Allen fantasized about committing mass murder. Until the end of his life, Allen denied that he was the Zodiac, or that he had killed anybody.

Inspectors Carroll and Maloney say the new DNA lab results eliminate Allen as the person who licked the envelopes and stamps from the confirmed Zodiac letters.

And now, say the inspectors, they may have evidence that will lead to the killer’s identity.