Olig1

Olig1 and Olig2, which have been implicated in oligodendrogenesis, are expressed in the region of the ventral ventricular zone of late embryonic spinal cord where oligodendrocyte progenitors appear. Olig3 is transiently expressed in different types of progenitors of embryonic central nervous system and then disappears in the course of development. In adult, expression of Olig3 is primarily detected in neural tissues.

Olig1  is also strongly expressed in oligodendrogliomas, while expression is weak to moderate in astrocytomas. Expression in glioblastomas is highly variable

General Reference:

Igor Jakovcevski and Nada Zecevic. Olig Transcription Factors Are Expressed in Oligodendrocyte and Neuronal Cells in Human Fetal CNS. The Journal of Neuroscience, November 2, 2005 25(44):10064 –10073.