Const. Michael Russell says the test was conducted after the man was identified through a tip as possibly being Dunahee.
Police have been searching for Dunahee since March 24, 1991, when the then four-year-old boy disappeared from a playground at Blanshard Elementary School in Victoria while his parents and other adults were close by.
The disappearance — labelled an abduction the following day — sparked one of the largest child abduction investigations in Canadian history, involving nearly 100 police officers from the region and across B.C.'s Lower Mainland.
Last year, the family of the missing boy issued an age-enhanced composite picture estimating what Dunahee would look like as a 26-year-old man.
The unidentified Surrey man uploaded a recent picture of himself to a Vancouver Canucks online discussion forum to allow the users to compare it against the composite, and against older images of the missing boy.
The man went on to say that he is 26, around the same age Dunahee would be today, and explained that he remembers moving around a lot when he was young. He also said his father left the family when he was around 10, and his mother passed away earlier this year.
The forum topic thread has since been removed from the site out of concerns for the man's privacy.