TABLE 3.
Phenotypic abnormalities of Meckel’s cartilageconnected with abnormal gene expression.
| Genotype | Impact | References |
|
Alk2fl/fl; Wnt1-Cre (Bc-MP type I receptor) |
missing distal extremity of MC | Dudas et al., 2004 |
| c-Fos–/– | persistence of MC beyond juvenile stage | Anthwal et al., 2017 |
| Ctgf–/– | MC deformations | Ivkovic et al., 2003 |
| Dlx2–/– | abnormal posterior MC, malformed middle ear ossicles | Depew et al., 2005 |
| Dlx5–/– | MC is shortened and its path back toward the middle ear is disrupted | Depew et al., 2005 |
| Dlx5/6–/– | complete loss of MC | Robledo et al., 2002 |
|
Dmm/Dmm (semi-dominant Col2a1 mutation) |
growth retardation of MC, osteoarthritis | Ricks et al., 2002 |
|
Ednra constituative activation Ednta fl/fl; Wnt1-Cre Egfr–/– |
transformed upper jaw, with duplication MC duplicated maxilla, loss MC MC deformations |
Sato et al., 2008 Ruest and Clouthier, 2009 Miettinen et al., 1999 |
|
Endothelin −/− Fgfr3Y367C/+ |
defect lower jaw, vestigial MC shortened hypertrophic zone of MC, achondroplasia |
Ozeki et al., 2004 Duplan et al., 2016 |
| Fgf8neo/– | absent or hypoplastic MC | Abu-Issa et al., 2002 |
| Fuz–/– | hyperplastic malformed MC | Zhang et al., 2011 |
|
Hand 2 fl/fl; Wnt1-Cre Isl1fl/fl; Shh-Cre |
duplicated mandible and MC smaller MC (E13.5), lack of cartilage at the distal tip resulting in fused growth of two ossifying elements |
Funato et al., 2016 Li et al., 2017 |
| Nog–/– | increased size of MC (due to proliferation) endochondral-like ossification of intermediate part | Wang et al., 2013 |
| Runx2–/– | two ectopic cartilaginous processes in MC (indirect effect of missing bone) | Shibata et al., 2004 |
| Setdb1fl/fl; Wnt1-Cre | enlarged MC resulting from increased proliferation and hyperplasia, increased hypertrophy | Yahiro et al., 2017 |
| Shhfx/–; Nkx2.5-Cre | no apparent MC from E14.5 | Billmyre and Klingensmith, 2015 |
| Shh–/– | hypoplastic mesenchymal condensation, no apparent MC | Melnick et al., 2005 |
| Snai1flox/– Snai2–/–; Wnt1-Cre | overall shorter length, missing rostral MC and midline fusion | Murray et al., 2007 |
| Sox9fl/fl; Wnt1-Cre | total absence of MC | Mori-Akiyama et al., 2003 |
| Sox9 +/– | MC interrupted and bent toward the body appearing as shortened, campomelic dysplasia | Bi et al., 2001 |
| Tgfbr2fl/fl; Wnt1-Cre (E14.5) | curvy shape of MC, un-uniform thickness, disrupted perichondrium | Oka et al., 2007 |
| Tgfβ2 –/– | abnormal shape of MC | Sanford et al., 1997 |
|
Vegfafl/fl;Wnt1-Cre (E17.5) |
mandibular hypoplasia, decreased size of MC resulting from abnormal vascularisation | Wiszniak et al., 2015 |