Sadly a match was not found and Chace died in June 2012.
Although there are now 22 million people on the international registry, there are currently only about 8000 people registered as Maori and Pacific Islander on the donor registry in New Zealand.
Since forming the Dream Chaser Foundation _ A Chace Topperwien Charity, the couple have embarked on a national bone marrow drive and, next week, will be at Waikato University looking for potential donors.
"We try and follow the New Zealand Blood Drive people around the country," Mr Topperwien said.
"University's are ideal places to go because of the age of the students. You could pretty much say we pounce on anyone who looks like they may be of ethnic minority and explain to them the benefits of becoming a donor."
Last time the couple were at Waikato, they helped 50 people join the registry.
'We do have people say to us that the body is tapu but, to counter that, we tell them if they are a match with someone, their genetic paths have crossed somewhere along the line.
"Whakapapa is so important to Maori so we tell them that by not becoming a donor, there is a chance the whakapapa of a whanau could cease."
Mr Topperwien said it had been interesting to learn most international bone marrow matches for Maori come from Germany.
"We've been told time spent in Germany by Maori soldiers may have something to do with it," he laughed.
He said a lack of understanding of how to become a donor also plays a part.
"I urge people to sign up and become a potential lifesaver," Mr Topperwien said. Once they leave Hamilton, the Topperwiens will be travelling to Starship Hospital where the hope to catch up with Mikaera Tamihere and his whanau.
'The New Zealand Blood Service is next in Whakatane on Tuesday, August 5. They will be at the Whakatane RSA, 13 Richardson Street between 11.30am and 3pm.