- This is a Chinese name; the family name is Tsien.
Roger Yonchien Tsien (simplified Chinese: 钱永健; traditional Chinese: 錢永健; pinyin: Qián Yǒngjiàn; February 1, 1952 – August 24, 2016) was a Chinese-American biochemist. He was a professor of chemistry and biochemistry at the University of California, San Diego. He was awarded the 2008 Nobel Prize in Chemistry for his discovery and development of the green fluorescent protein with organic chemist Osamu Shimomura and neurobiologist Martin Chalfie.