IDH1 and brain neoplasm: Several studies have explored numerous potential genetic risk factors for primary brain tumors, such as ATM serine/threonine kinase (ATM), cyclin dependent kinase inhibitor 2A (CDKN2A), isocitrate dehydrogenase (NADP(+)) 1/2 (IDH1/IDH2), erb-b2 receptor tyrosine kinase 2 (ERBB2, also named as HER2), neurofibromin 1 (NF1), NF2, moesin-ezrin-radixin-like (MERLIN) tumor suppressor (NF2), phosphatase and tensin homolog (PTEN), RB transcriptional corepressor 1 (RB1), tumor protein p53 (TP53), and germline genetic variants (SNPs, single nucleotide polymorphisms) [16,17].