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Autophagy associated genes (ATGs) played an important role in the repair process of DNA damage and decreased autophagy may weaken the repair process and aggravate DNA damage. Based on this, we hypothesized that DNA damage levels might be modified by genetic variants in autophagy associated genes. In order to validate our hypothesis, 307 subjects were recruited from three different cities (Zhuhai, Wuhan and Tianjin) in China. Demographic data, individual 24-h PM 2.5 exposure and peripheral blood DNA damage levels were also detected. Seven potentially functional polymorphisms in four essential autophagy associated genes ( ATG5 , ATG7 , ATG8 and ATG13 ) were screened to evaluate the relationship between the polymorphisms of autophagy associated genes and DNA damage levels. This association was assessed by using multivariable linear regression model, age, sex, smoke and PM 2.5 exposure levels were adjusted in each city. We found that rs12599322 in ATG8 (A > G, β = 0.263, 95% CI: 0.108–0.419, P = 8.98 × 10 − 4 ) and rs7484002 in ATG13 (A > G, β = 0.396, 95% CI: 0.085–0.708, P = 0.013) were significantly associated with higher DNA damage levels. Furthermore, functional annotations showed that both rs12599322 and rs7484002 located at transcription factor binding sites (TFBS), indicating that they could regulate the expression of related genes through TF regulation. Following allelic trend analysis revealed that the DNA damage levels were significantly aggravated with the increasing number of risk variants in autophagy associated genes ( P for trend: 8.09 × 10 − 5 ). Our findings suggested that the polymorphisms in ATGs may influence DNA damage levels in one of the Chinese population. [ABSTRACT FROM AUTHOR]

Abstract: Autophagy is a cellular process directed at recycling of cellular proteins and removal of intracellular microorganisms, which is important for balancing sources of energy at critical times in development and in response to nutrient stress. It has been reported to be a critical process in cancer initiation and progression. We hypothesized that genetic variants in critical genes of autophagy may be involve in the development of breast cancer. Thus, we systematically screened 14 potentially functional polymorphisms in six autophagy-related genes (ATG3, ATG5, ATG7, ATG10, and ATG12 and LC3) that are core components in autophagosome formation. We conducted a case-control study including 1064 breast cancer cases and 1073 cancer-free controls to evaluate the associations of these variants with breast cancer risk. We found that rs1864182 and rs10514231 in ATG10 were significantly associated with a decreased risk of breast cancer [odds ratios (OR)=0.77, 95% confidence interval (CI): 0.61–0.96, P =0.023; and OR=0.75, 95% CI: 0.59–0.93, P =0.010, respectively]. Similar protective effects for both loci were observed between subgroups stratified by ages at diagnosis/recruitment, menarche and first live birth, and status of menopause, estrogen receptor (ER) and progesterone receptor (PR). These results suggest that genetic variants in ATG10 may implicate with breast cancer susceptibility in Chinese population. Further large and functional studies are needed to confirm our findings. [Copyright &y& Elsevier]