Table 1. Summary of En1/2 and En1 conditional mutant phenotypes.

			Phenotype
Genotype						Cb subregions
En1 alleles	En2 alleles		SC	IC	Cb size	aV (I-V)	pV (VIII)	pH (CII/PM)
−/−	−/−		X	X	X
−/−	−/+
flox/Cre	−/−
Denki/Denki	−/−		X/√	X	X
flox/Cre	−/+		√√	X	X
−/−	+/+		√√/√	X	(√)
−/+	−/−		√√√	√/X	√	√	√/X	√√*
Denki/+	−/−		√√√	√√	√√	√√	X	√√*
(ψ) Denki/Denki	+/−		√√√	√√	√√	√√	X	√√√
2ki/−	−/−		√√√	√√	√√	√√√	√	√√
+/+	−/−		√√√	√√√	√√	√√√	√	√√
flox/Cre	+/+		√√√	√	√√√	√√/√√√	√√√	√√√
−/+	−/+		√√√	√√√	√√√	√√	√√	√√√
2ki/2ki	−/−		√√√	√√√	√√	√√√	√√√	√√
2ki/2ki	−/+		√√√	√√√	√√√	√√√	√√√	√√√
2ki/2ki	+/+
Denki/Denki	+/+
+/+	−/+
−/+	+/+
+/+	+/+

En1/2 alleles: +, wild type; −, null. SC/IC: √√√, normal superior/inferior colliculus; √√, reduced in size; √, little formed; X, not formed. Cb size: √√√, normal; √√, ∼1/3 overall reduction; √, ∼1/2 overall reduction; (√), only the most lateral tissue remains; X, not formed. Anterior vermis (aV): √√√, normal folia I-V; √√, fusion and smaller folia I-III; √, fusion and smaller folia I-V. Posterior vermis (pV): √√√, folium VIII is associated normally with folium VII; √√, folium VIII is positioned between lobule VII and IX; √, folium XIII is smaller and associated with folium IX; X, little or no folium VIII. Posterior hemisphere (pH): √√√, crusII and paramedian folia are normal; √√, crusII and paramedian folia are fused; √√*, one mutant had a partial fissure separating crusII and paramedian. ψ, denotes the mutants that survived into adulthood and that were analyzed.