Zienolddiny S, Haugen A, Lie JA, Kjuus H, Anmarkrud KH, Kjærheim K. Breast Cancer Res. 2013;15(4):R53.
To determine biomarkers for the risk of breast cancer in night shift workers, a genetic case-control study in Norwegian nurses was conducted. The participants were 1,182 women ages 35 to 74 years who had worked as nurses for at least one year. They were genotyped, had their breast cancer statuses determined from the Cancer Registry of Norway, and their work records recorded to assess exposure to shift work.
After adjusting for several confounding variables, those homozygous for the C variant of rs4238989 and the G variant of rs3760138 in the aanat gene had an increased risk of cancer. Additionally, those homozygous for the T variant of rs2278749 in the bmal1 gene and the T variant of rs3749474 in clock had reduced risk of breast cancer.
Additionally, a statified analysis was performed, showing associations between variants in aanat (rs3760138 and rs4238989), clock (rs3749474), ror-b (rs3903529, rs3750420), mtnr1a (rs131113549), bmal1 (rs2290035, rs969485 rs2278749), bmal2 (rs2306074), csnk1e (rs5757037), npas2 (rs17024926) and per3 (rs1012477) and cancer. The exact associations depend on short and long term (>5 years of work) exposure to night work and the maximum number of consecutive night shifts.
All of these results were found to be noteworthy in a post hoc multiple comparisons procedure.
SNPs in aanat
SNPs in bmal1
rs2306074 in bmal2
rs3749474 in clock
rs1012477 in per3
SNPs in ror-b
rs5757037 in csnk1e
rs17024926 in npas2