The results of subgroup analysis show that the highest association between ATM variants and the risk of breast cancer belongs to the Asian population with an odds ratio of 4.21 (95%CI: 0.78–22.88; I square: 89.5%; PI square: 0.0001) while the lowest odds ratio was among the European population that was equal to 1.24 (95% CI: 0.94–1.64; I square: 18.5%; PI square: 0.297). Here, ATM is linked to breast cancer.