Two female DNA profiles have been recovered after a husband and wife were found slain in their home in Florida a year ago, but no suspects have been identified, police say.

The bodies of David Pichosky and Rochelle Wise of Toronto were found in their Hallandale Beach home on Jan. 10, 2013, after concerned friends reported they hadn't picked them up as scheduled the previous day.

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David Pichosky, 71, and Rochelle Wise, 66, were found dead in their Florida home on Jan. 10, 2013. (CBC)

Police said Pichosky and Wise were bound and died of asphyxiation, but no further details have been released.

At a news conference Wednesday morning, Hallandale Beach police said the DNA profiles of two women were recovered from the crime scene. The DNA doesn't match anyone who would have had access to the home, nor has a match been found in the FBI's database.

"It's a very complex case," said police Chief Dwayne Flournoy. "You have a profile of two females inside of a double homicide. That in itself is unique ... It doesn't match typically what happens in homicide cases."

Last February, police released video from a neighbour's surveillance camera hoping to identify a woman seen walking to the rear of the couple's home, but Flournoy said the woman still has not been identified.

"We believe the identification of this female is critical and important to this case," he said.

Police believe the slayings may have been motivated by robbery as Wise's unique wedding band — valued at $16,000 — was the only item missing from the couple's condo. Police said the ring has a unique clasp that allows it to be put on without going over the knuckle, designed to accommodate Wise's arthritis.

Flournoy said there's been no sign of the ring since the attack, and there haven't been any attempts to use the couple's credit cards.

He said it's not clear if the couple was targeted or if it was a crime of opportunity, but the couple probably didn't know their attackers.

'Every day is a nightmare'

Investigators haven't identified a vehicle associated with the homicide, Flournoy said, even though the couple lived in a gated community. He said the suspects were probably inside the condo for quite some time.

Members of Pichosky's family also appeared at Wednesday's news conference, pleading for anyone with information to come forward.

"As horrible as we all know murders are, we never think it would happen to someone we love," said Sari Rosenblum, Pichosky's daughter.

"Over the past 12 months, we have learned to live in a new reality. The sun comes up, the birds may be singing but for our family, every day is a nightmare."

A partial shoe print that was found at the scene has been identified as an Adidas shoe out of production since 2000. The largest model of shoe that sole was used on was the Supernova, Flournoy said. Investigators were not able to determine its size, nor whether it was a man's or woman's shoe, he said.

More than 50 people have been interviewed during the investigation.

The reward for information in the couple's slaying has been increased to $57,000. Tips must come to investigators through Crime Stoppers.

With files from The Canadian Press