1 Title: N-acetyltransferase 2 polymorphism and breast cancer risk with smoking: a case control study in Japanese women Akio Hara 1,2 • Naruto Taira 1,2 • Taeko Mizoo 1,2 • Keiko Nishiyama 1,2 • Tomohiro Nogami 1,2 • Takayuki Iwamoto 2 • Takayuki Motoki 2 • Tadahiko Shien 1,2 • Junji Matsuoka 2 • Hiroyoshi Doihara 1,2 • Setsuko Ishihara 3 • Hiroshi Kawai 4 • Kensuke Kawasaki 5 • Youichi Ishibe 6 • Yutaka Ogasawara 5 • Shinichiro Miyoshi 1 1 Department of General Thoracic Surgery and Breast and Endocrinological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan 2 Department of Breast and Endocrinological Surgery, Okayama University Hospital, Okayama, Japan 3 Department of Radiology, Okayama Saiseikai General Hospital, Okayama, Japan 4 Department of Breast Surgery, Okayama Rousai Hospital, Okayama, Japan 5 Department of Breast and Endocrinological Surgery, Kagawa Prefectural Central Hospital, Kagawa, Japan 6 Department of Breast Surgery, Mizushima Kyodo Hospital, Okayama, Japan Corresponding Author: Naruto Taira Mailing address: Department of General Thoracic Surgery and Breast and Endocrinological Surgery, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, 2-5-1 Shikata-cho, Kita-ku, Okayama-city, Okayama 700-8558, Japan Phone: +81-86-235-7265 Fax: +81-86-235-7269 E-mail: ntaira@md.okayama-u.ac.jp Keywords: breast cancer, Japanese, NAT2, single nucleotide polymorphism, smoking