Probe:	ChM-I cDNA4
Probe preparation:	Antisense labelled with digoxigenin RNA
Visualized with:	Alkaline phosphatase

Structure	Level	Pattern	Image	Note
TS21: cartilage	Present	Widespread	4A
TS21: vertebral cartilage condensation	Strong		4B , 4A
TS21: notochord	Absent		4B , 4A
TS21: nasal septum mesenchyme	Present		4A	Expressed in the nasal septum cartilage.
TS21: rib cartilage condensation	Present		4A
TS21: trachea	Present	Regionally restricted	4A	Expressed in trachea cartilaginous rings.

Structure	Level	Pattern	Image	Note
TS21: hindlimb phalanx pre-cartilage condensation	Present		4C

Structure	Level	Pattern	Image	Note
TS24: vertebral cartilage condensation	Present	Regionally restricted	5A	Expression declined in the late hypertrophic chondrocytes.

Structure	Level	Pattern	Image	Note
TS24: Meckel's cartilage	Present	Regionally restricted	5C	Expressed in the prehypertrophic and early hypertrophic zones, but were completely abolished in the late hypertrophic zone.

Structure	Level	Pattern	Image	Note
TS21: bony labyrinth	Present		5D	Expressed to a lesser extent in chondrocytes surrounding the auditory canal.

Structure	Level	Pattern	Image	Note
TS21: chondrocranium pre-cartilage condensation	Present		5E	In addition to the chondrocranium, expressed in immature osteoblasts in the dermocranium.

Structure	Level	Pattern	Image	Note
TS20: cochlear duct	Present		5F	Expressed in the lateral wall.

Structure	Level	Pattern	Image	Note
TS18: skeleton	Present	Regionally restricted		Expressed in cartilage in the occipital bone rudiment.
TS18: trunk mesenchyme	Weak	Regionally restricted		Expressed in the intermediate mesoderm flanking notochord.

Structure	Level	Pattern	Image	Note
TS21: neural retina	Present