haplogroup N9b
References
Nishigaki Y, Yamada Y, Fuku N, Matsuo H, Segawa T, Watanabe S, Kato K, Yokoi K, Yamaguchi S, Nozawa Y, Tanaka M. Mitochondrial haplogroup N9b is protective against myocardial infarction in Japanese males. Hum Genet. 2007 Feb;120(6):827-36. PMID: 17033820