Table 4 Single and multiple loss-of-function homozygote mutations in Hox4 and Hox5 paralog group (PG) and effect on the axial skeleton in the mouse, in particular focusing on the cervical vertebral column. Mutations in Hox3 and Hox6 PG also affect vertebral development, but are usually confined to the atlanto-occipital and thoracic region [75, 76]. Ref. = references

Hox4 PG

(excl. HoxC-4)

-

CV2-5

(partial) anterior transformation

CV2-5 developing C1-type characteristics

[40]

HoxA-4

Hox-1.4

CV3

partial anterior transformation

CV3 developing CV2-type neural spine

[38, 39]

CV7

posterior transformation

cervical ribs at CV7

HoxB-4

Hox-2.6

CV2

partial anterior transformation

CV2 developing anterior arch and extra ventral tubercula

[77]

HoxC-4

Hox-3.5

CV7

partial posterior transformation

cervical rib heads on CV7

[78]

TV3

anterior transformation

prominent spinous process on TV3

TV8

anterior transformation

vertebrosternal ribs on TV8

HoxD-4

Hox-4.2

/-5.1

CV1-CV3

anterior transformation

fusion of neural arches at CV1-3

[79]

CV2

anterior transformation

CV2 developing anterior arch, CV1-type lateral articular surfaces

CV7

posterior transformation

cervical ribs at CV7

Hox5 PG

-

CV3-TV2

anterior transformation

CV3-TV2 developing C2-type characteristics

[63]

CV7

anterior transformation

CV7 developing CV6-like transverse foramina

HoxA-5

Hox-1.3

CV6

anterior transformation

absence of ventral tubercula on CV6

[61, 62]

CV7

partial posterior transformation

cervical ribs on CV7

LV1

anterior transformation

thoracic ribs on LV1

HoxB-5

Hox-2.1

CV6

anterior transformation

absence of ventral tubercula on CV6

[32]

CV7

anterior transformation

CV7 developing CV6-like ventral tubercula, transverse foramina

TV1

anterior transformation

absence of ribs on TV1

shoulder girdle

rostral shift of shoulder girdle

forelimbs shifted anteriorly

HoxC-5

Hox-3.4

-

-

-

-