It's interesting to note that two of Japan's four ice dance teams have a non-Japanese partner.
Bryna OI of OI / MIZUTANI is American. She was 5th at 2009 New England Novice Regionals as a single. She switched to dance and was 6th at 2011 US Novice Nationals with partner Mark Jahnke. In the fall of 2011 she teamed with Taiyo Mizutani; they competed at 2012 Japanese Nationals and won in the absence of Reed/Reed, who were out with injury.
Marien De La Asuncion of HIRAI / DE LA ASUNCION previously competed for France with 3 different partners. He teamed up with Emi Hirai in 2011 after Emi's partnership with Taiyo Mizutani broke up (he teamed with Bryna Oi); they competed at 2012 Japanese Nationals and were second behind Oi / Mizutani.
You have to wonder why Japanese skaters pursue partnerships with non-Japanese partners (both male and female) knowing there is no hope of competing with those partners at the Olympics.