In 1976, the Nurses’ Health Study (NHS) was launched with the goal of studying women’s health [10]. Since that time, 121,700 nurse participants have answered biennial questionnaires (response rate >90% over time) about personal and physical characteristics, physical activity and ability, reproductive history, family history of disease, environmental/personal exposures, diet and dietary supplements, screening, disease and health conditions, prescription and over-the-counter medications, and psychosocial history. In addition, 32,826 blood and 29,684 cheek cell samples have been collected since the late 1980s. An additional 116,430 nurses were recruited in 1989 as a part of Nurses’ Health Study II (NHSII) and have returned biennial questionnaires similar to those used for NHS [11]. For NHSII, we have collected blood samples for 29,612 women and cheek cell samples for an additional 29,859 women. The Health Professional Follow-Up Study (HPFS) began in 1986 with the aim of studying men's health [12]. A total of 51,529 men in health professions were recruited, and every two years, members of the study receive questionnaires similar to the ones used in NHS. In HPFS, we have collected blood samples
