Table 4.

Frequency of Selection of Restricted cDNAs in Different Expression Screens

Reference	Species	Stages screened	cDNA library	Library type	Number of clones screened	Restricted cDNAs
This study	Mouse	6.5—9.5 dpc	7.5-dpc endoderm	Parent	160	18%
Neidhardt et al. 2000	Mouse	9.5 dpc	9.5-dpc embryo	Parent	989	6%
Neidhardt et al. 2000	Mouse	9.5 dpc	9.5-dpc embryo	Subtracted	3737	7%
Neidhardt et al. 2000	Mouse	9.5 dpc	9.5-dpc embryo	Normalized	622	18%
Reymond et al. 2002	Mouse	9.5 dpc	Orthologues of human chromosome 21 genes	—	158	21%
Reymond et al. 2002	Mouse	10.5 dpc	idem	—	158	28%
Reymond et al. 2002	Mouse	14.5 dpc (sections)	idem	—	158	42%
Gitton et al. 2002	Mouse	9.5 dpc	idem	—	158	21%
Christiansen et al. 2001	Chick	HH^* 9—12	Hindbrain HH^* 10—11^a	Subtracted	445	8%
Kudoh et al. 2001	Zebrafish	Shield, 3 somites, 15 somites, 24 hpf	Early somitogenesis embryo	Normalized	2765	13%
Gawantka et al. 1998	X. laevis	Stages 10+, 13, 30	Neurula stage embryo	Parent	1765	25%^b

↵a Stage according to Hamburger and Hamilton (1951)
↵b This figure is reduced to 16% if one considers only unique cDNAs with a restricted expression pattern

Characterizing Embryonic Gene Expression Patterns in the Mouse Using Nonredundant Sequence-Based Selection