3-Methyladenine (3-MA) nbspis a methylated derivative of adenine that has been used as an In vivo marker for the methylation of DNA. 3-Methyladenine and 7-methylguanine are the two main N-methylpurines formed in DNA upon exposure to methylating agents. 3-MA is removed from damaged DNA via the DNA base excision repair pathway which begins with the enzyme N-methylpurine DNA glycosylase. The dependence of 3-MA repair on nucleotide excision repair in mammalian cell lines has been studied.3-MA have been widely used as autophagy inhibitor based on its inhibitory effect on class I and class III PI3K activity which is known to be essential for induction of autophagy. 3-MA blocks class I PI3K persistently whereas its suppressive effect on class III PI3K is transient understanding the dual role of 3-MA in autophagy thus suggests that caution should be exercised in the application of 3-MA in autophagy study.furthermore 3-MA is also capable of making the reduction of lymphocyte number caused