Reporter:	lacZ
	Direct Detection

Structure	Level	Pattern	Image	Note
TS20: rib pre-cartilage condensation	Present		2a , 2b	Expression is present in chondrocytes. There is a lack of staining in the surrounding mesenchyme and stroma.
TS20: vertebral pre-cartilage condensation	Present		2a	Expression is present in chondrocytes.
TS20: telencephalon	Present		2a	Expression is present in the neuroepithelium.
TS20: nose	Present		2a	Expression is present in the snout region.
TS20: dermis	Present		2a
TS20: heart	Present		2a
TS20: cranium	Absent		2a	There is no expression in the frontal and parietal bones of the skull, bones that form without a cartilaginous anlage.

Structure	Level	Pattern	Image	Note
TS21: forelimb pre-cartilage condensation	Present		2c	Expression is present in all cartilaginous anlagen of developing limb bones, as well as in the perichondrium.
TS21: forelimb epithelium	Present	Regionally restricted	2c	Expression is present in the dermis.
TS21: forelimb mesenchyme	Ambiguous		2c	The mesenchyme and stroma are largely negative.

Structure	Level	Pattern	Image	Note
TS28: femur	Present	Regionally restricted	2e , 2f	Expression is present in the articular cartilage, growth plate, and perichondrial/periosteal region. It is not present in the bone tissue.

Structure	Level	Pattern	Image	Note
TS27: femur	Present	Regionally restricted	2g	Expression is present in reserve and proliferative zones of the growth plate, as well as in the perichondrium, but it is not present in the hypertrophic zone.