Influence of altered circadian rhythm on breast cancer was first noted in 1960s [1].Environmental factor altered light and dark cycles such as those experienced by night shift workers can also affect incidence of BC.Hormonal receptor status also plays an important role in BC associated with night work higher expression of Positive estrogen receptorand positive Human Epidermal growth factor 2 receptor cancer [2]. The gene discussed is ERBB2; the disease is breast carcinoma.