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The origin and the diversity of cortical interneurons have been extensively investigated.Recent studies, using genetic fate mapping, reveal the lateral/caudal ganglionic eminence (LGE/CGE) contribute large population of interneurons to the upper layers of the cortex.However, less is known about this population of cortical interneurons compared with the well characterized MGE derived ones, because of no specific markers available except the recently found CGE lineage marker serotonin 5-hydroxytryptamine 3A (5-HT3A) receptor.Here we show that the zinc finger transcription factor SP8 specifically labels cohorts of mice cortical interneurons originating in the dorsal LGE (dLGE) and dorsal CGE (dCGE).SP8-expressing interneurons initially migrate from rostral dLGE to invade the cortex at embryonic 12.5 (E12.5), then from both dLGE and dCGE since E13.5.They tangentially migrate through and accumulate in the subventricular/intermediate zone (SVZ/IZ), and only at late embryonic stage and first postnatal week radially migrate into the cortical plate and the marginal zone.SP8-expressing dLGE/dCGE derived interneurons preferentially occupy superficial cortical layers and account for one fifth of all cortical interneurons in adult brain.These results indicate that cortical interneurons have more heterogeneous origins and subtypes.