Figure 1.

Olfactory receptor genes whose expression in the mouse olfactory epithelium was confirmed in this study. Genes whose expression has been confirmed by our cDNA screen are colored blue on a phylogenetic tree of 1,107 intact mouse olfactory receptors. Genes whose expression was confirmed by PCR methods are colored red (genes listed in Additional data file 1 were confirmed by specific PCR of the cDNA library or reverse-transcribed RNA, and genes confirmed using the class I degenerate primer for RT-PCR are AY317681, AY317698, AY317700, AY317767, AY317773, AY317774, AY317797 and AY317923). Other olfactory receptors are colored gray, and a chemokine outgroup is colored black. Class I olfactory receptors are bracketed, and the remaining olfactory receptors are class II.