Probe:	Shox2 cDNA2
Probe preparation:	Antisense labelled with digoxigenin RNA

Structure	Level	Pattern	Image	Note
TS15: forelimb bud mesenchyme	Present	Regionally restricted	1A	Stronger expression in dorsal regions.

Structure	Level	Pattern	Image	Note
TS17: forelimb bud mesenchyme	Present	Regionally restricted	1B	Expression restricted to proximal limb mesenchyme, with stronger expression remaining in dorsal regions.

Structure	Level	Pattern	Image	Note
TS19: future arm mesenchyme	Present	Regionally restricted	1C	Strong expression in proximal limb mesenchyme associated with stylopodial cartilaginous elements. Relatively weak expression in mesenchymal tissues surrounding future zeugopodial condensations.

Structure	Level	Pattern	Image	Note
TS20: upper arm rest of mesenchyme	Present	Regionally restricted	1D	Expression in mesenchyme of proximal limb surrounding cartilaginous elements.
TS20: humerus pre-cartilage condensation	Weak	Regionally restricted	1D	Weak expression in chondrocytes in both ends of humerus.

Structure	Level	Pattern	Image	Note
TS21: humerus cartilage condensation	Present	Regionally restricted	1E	Expression in immature (proliferating) chondrocytes.
TS21: upper arm rest of mesenchyme	Present	Regionally restricted	1E	Strong expression in perichondrium of humerus. Expression downregulated in surrounding connective tissue .

Structure	Level	Pattern	Image	Note
TS22: humerus cartilage condensation	Present	Regionally restricted	1F	Expression in immature (proliferating) chondrocytes.
TS22: upper arm rest of mesenchyme	Present	Regionally restricted	1F	Strong expression in perichondrium of humerus. Expression downregulated in surrounding connective tissue .