Table 1.

Summary of studies on direct reprogramming to specific neural subtypes.

species	neural subtype	factors	original cell	efficiency	action potential	synaptic competence	ref
mouse	excitatory neuron	Pax6	postnatal astrocyte	Tuj1 (+): 50-60%	ND	ND	[8]
		Ngn2		Tuj1 (+): 71%	OK	OK	[47]
		Ascl1		Tuj1 (+): 37%	OK	OK	[47]
		Ngn2		MAP2 (+): 91%	OK	OK	[48]
		Ascl1, Brn2, Myt1l	MEF	Tuj1 (+): 20%	OK	OK	[26]
		Ascl1		Tau (+): 10%	OK	OK	[49]
		Ascl1, Brn2, Myt1l	hepatocyte	Tau (+): 5%	OK	OK	[27]
	dopaminergic neuron	BAM, Lmx1a, FoxA2	MEF	TH (+): 10%	OK	ND	[50]
		Ascl1, Lmx1a, Nurr1	MEF	TH (+): 18%	OK	ND	[51]
		Ascl1, Lmx1a, Nurr1, Foxa2, En1, Pitx3,	TTF	TH (+): 9.1%	OK	ND	[52]
	inhibitory neuron	Dlx2	postnatal astrocyte	Tuj1 (+): 93%	OK	OK	[48]
	spinal motor neuron	BAM, Lhx3, hb9, Isl1, Ngn2	MEF, TTF	Hb9 (+): 5-10% (MEF)	OK	OK	[53]
	retinal ganglion like cells	Ascl1, Brn2, Ngn2	MEF, ETF (adult ear fibroblast)	RPF1 (+): 5% (MEF), <1% (ETF)	OK	ND	[54]
	neural precursor cell	Sox2, Brn2, Foxg1	MEF	ND (proliferating)	OK (iNPC derived neuron)	ND	[55]
	oligodendrocyte precursor cell	Sox10, Olig2, Zfp536	MEF	ND (proliferating)	ND	ND	[56]
human	excitatory neuron	Ascl1, Brn2, Myt1l, NeuroD1	embryonic, postnatal fibroblast	TUJ1: 2-4%	OK	OK	[32]
		Ascl1, NeuroD2, Myt1l, miR-9/9*, miR-124	postnatal, adult fibroblast	postnatal: Tuj1 (+) 4-8 % adult: Tuj1 (+) 1-11%	OK	OK	[37]
		Brn2, Myt1L, miR-124	postnatal, adult fibroblast	postnatal: Tuj1 (+) 4-5 % adult: Tuj1 (+) 1.5-11.5%	OK	ND	[38]
	immature neuron	Ascl1	fetal fibroblast	ND	OK	ND	[49]
	dopaminergic neuron	BAM, Lmx1a, FoxA2	embryonic, postnatal fibroblast	TH (+): 10%	OK	ND	[50]
		Ascl1, Lmx1a, Nurr1	fetal, adult fibroblast	TH (+): 3%	OK	ND	[51]
	spinal motor neuron	BAM, Lhx3, Hb9, Isl1, Ngn2, NeuroD1	embryonic fibroblast	Hb9 (+): 0.03%	OK	ND	[53]
	inhibitory neuron	Bcl11B, Dlx1, Dlx2, Myt1l, miR-9/9*, miR-124	postnatal, adult fibroblast	MAP2: 90% TUJ1: 87%	OK	OK	[57]