IDH1 and diffuse astrocytoma: In line with many previous studies [3-5,12,15,19-22], that reported a higher frequency of IDH1 mutations in grade II gliomas compared with grades III and primary glioblastoma, the current showed highest IDH1 mutations among low-grade diffused astrocytomas (62.5%), and in secondary glioblastoma (88.88%), between other grades and types of gliomas.