Table 4.

Id gene knockout studies in mice

Deleted gene	Phenotype
Id1−/−	Decreased neovascularization [146]
Id2−/−	Lack of Langerhans and splenic dendritic cells, reduced number of NK cells, altered peripheral lymphoid organs [143, 147]
Id3−/−	Defects in B-cell activation and proliferation upon B-cell receptor signaling, and in both negative and positive selection of T-lineage progenitors [144, 145]
Id4−/−	Altered brain size, defects in forebrain development [142, 148]
Id1−/−, Id3−/−	Embryonic lethality with cranial hemorrhage, small brain size, premature neural differentiation [149]