Phenotypes associated with this allele

• Allele Symbol: Prrx2^tm1Hubr
• Allele Name: targeted mutation 1, Hubrecht Institute
• Allele ID: MGI:1857641
• Summary: 4 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Prrx2^tm1Hubr/Prrx2^tm1Hubr	involves: 129P2/OlaHsd * FVB	MGI:3698247
cx2	Prrx1^tm1Tex/Prrx1^tm1Tex Prrx2^tm1Hubr/Prrx2^tm1Hubr	involves: 129P2/OlaHsd * 129S7/SvEvBrd * FVB	MGI:2168063
cx3	Prrx1^tm1Tex/Prrx1^+ Prrx2^tm1Hubr/Prrx2^tm1Hubr	involves: 129P2/OlaHsd * 129S7/SvEvBrd * FVB	MGI:3698248
cx4	Prrx1^tm1Tex/Prrx1^tm1Tex Prrx2^tm1Hubr/Prrx2^+	involves: 129P2/OlaHsd * 129S7/SvEvBrd * FVB	MGI:3698249

Genotype
MGI:3698247

hm1

• Allelic Composition: Prrx2^tm1Hubr/Prrx2^tm1Hubr
• Genetic Background: involves: 129P2/OlaHsd * FVB

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

normal phenotype

no abnormal phenotype detected ( J:50488 )

• homozygotes are fertile and healthy, with a normal life span and no detectable skeletal or inner ear abnormalities

Genotype
MGI:2168063

cx2

• Allelic Composition: Prrx1^tm1Tex/Prrx1^tm1Tex; Prrx2^tm1Hubr/Prrx2^tm1Hubr
• Genetic Background: involves: 129P2/OlaHsd * 129S7/SvEvBrd * FVB

mortality/aging

neonatal lethality, complete penetrance ( J:50488 )

• in contrast to Prrx1^tm1Tex homozygotes which live up to 24 hrs, double homozygotes die within 1 hr after birth

respiratory system

respiratory distress ( J:50488 )

skeleton

abnormal cranium morphology ( J:50488 )

• the lateral wall of the skull is composed of a sheet of ectopic cartilage, as squamosal and zygomatic bones are absent

abnormal oval window morphology ( J:50488 )

• the oval window is displaced medially

absent Meckel's cartilage ( J:50488 )

• most of Meckel's cartilage is absent; only the distal tip and a small proximal part is present

absent temporal bone squamous part ( J:50488 )

absent zygomatic arch ( J:50488 )

• the entire zygomatic arch is absent

abnormal hyoid bone morphology ( J:50488 )

• the styloid process is abnormally fused to the hyoid bone

absent incisors ( J:50488 )

• mandibular incisors are either absent (38%) or a single median incisor is observed (42%)

• in contrast, molars appear unaffected

• in some cases, a rudimentary second incisor is observed (12%)

abnormal mandible morphology ( J:50488 )

• at E18.5, ~8% of double homozygotes show a cleft mandible and tongue

• dentaries are shortened and their distal tips fused

short mandible ( J:50488 )

• at E12.5, the lower jaw is much shorter than normal

absent maxillary shelf ( J:50488 )

absent maxillary zygomatic process ( J:50488 )

• the malar (zygomatic) process of the maxilla is absent

micrognathia ( J:50488 )

• severely reduced lower jaw

absent zygomatic bone ( J:50488 )

abnormal malleus morphology ( J:50488 )

• malformed malleus, with an ectopic process immediately distal from the malleus

abnormal stapes morphology ( J:50488 )

• the stylohyoid ligament is chondrified and connects the stapes and the styloid process to the lesser horn of the hyoid bone; as a result, the stapes is displaced

fused tarsal bones ( J:50488 )

• tarsal bones are fused with a variable pattern

bowed radius ( J:50488 )

abnormal ulna morphology ( J:50488 )

• the triangular, which articulates with the ulna and the carpal bones, is laterally truncated, and the pisiform is fused to the ulna

bowed ulna ( J:50488 )

abnormal tibia morphology ( J:50488 )

• the tibial diaphysis bulges out and forms a cap of bone under which the proximal and distal epiphyseal cartilages are connected

abnormal metatarsal bone morphology ( J:50488 )

• an ectopic cartilaginous element is seen between the first and second metarsal in the hindfoot

decreased width of hypertrophic chondrocyte zone ( J:50488 )

• in newborns, the zone of pre- and hypertrophic cartilage cells are severely shorterned in the zeugopods

abnormal scapular spine morphology ( J:50488 )

• ~60% of newborn double homozygotes show partial or complete absence of the spine of the scapula

• the extent of this defect is often variable between left and right sides of the same animal, and is first evident at E13.5

xiphoid process foramen ( J:50488 )

• a hole is noted in the xyphoid process of the sternum

absent pubic symphysis ( J:50488 )

• the pubic symphysis is absent, resulting in a gap between the pubic bones

abnormal thoracic vertebrae morphology ( J:50488 )

• all double homozygotes show absence of the dorsal processes of thoracic vertebrae

abnormal cervical atlas morphology ( J:50488 )

• all double homozygotes show absence of the dorsal processes of the cervical atlas

abnormal cervical axis morphology ( J:50488 )

• all double homozygotes show absence of the dorsal processes of the cervical axis

abnormal lumbar vertebrae morphology ( J:50488 )

• all double homozygotes show absence of the dorsal processes of lumbar vertebrae

abnormal vertebral arch morphology ( J:50488 )

• neural arches spread out laterally

absent vertebral arch ( J:50488 )

• the dorsal processes of the thoracic, lumbar and cervical vertebrae are absent

ectopic cartilage ( J:50488 )

• the lateral wall of the skull is composed of a sheet of ectopic cartilage, as squamosal and zygomatic bones are absent

• an ectopic cartilaginous element is seen between the first and second metarsal in the hindfoot

abnormal stylohyoid ligament morphology ( J:50488 )

• the entire stylohyoid ligament is chondrified, and connects the stapes and the styloid process to the lesser horn of the hyoid bone

delayed bone ossification ( J:50488 )

• delayed ossification of the radius and tibia

limbs/digits/tail

abnormal digit morphology ( J:50488 )

• the first digit of the forefoot is broader and its phalanges are thinned centrally

polydactyly ( J:50488 )

• an extra digit is observed on the posterior side of the forefoot and is often thinner than other digits

• the morphology of the extra digit ranges from a fragment of a metacarpal to a complete metacarpal with two phalages

• the metacarpal of the extra digit articulates with the triangular and the ulna

fused tarsal bones ( J:50488 )

• tarsal bones are fused with a variable pattern

abnormal forelimb morphology ( J:50488 )

• downward pointing of forelimbs

abnormal forelimb zeugopod morphology ( J:50488 )

• neonatal forelimb zeugopods are severely shortened, with their cartilaginous precursors already shortened and thickened at E13.5

bowed radius ( J:50488 )

abnormal ulna morphology ( J:50488 )

• the triangular, which articulates with the ulna and the carpal bones, is laterally truncated, and the pisiform is fused to the ulna

bowed ulna ( J:50488 )

abnormal hindlimb zeugopod morphology ( J:50488 )

• neonatal hindlimb zeugopods are severely shortened, with their cartilaginous precursors already shortened and thickened at E13.5

abnormal tibia morphology ( J:50488 )

• the tibial diaphysis bulges out and forms a cap of bone under which the proximal and distal epiphyseal cartilages are connected

abnormal metatarsal bone morphology ( J:50488 )

• an ectopic cartilaginous element is seen between the first and second metarsal in the hindfoot

craniofacial

abnormal cranium morphology ( J:50488 )

• the lateral wall of the skull is composed of a sheet of ectopic cartilage, as squamosal and zygomatic bones are absent

abnormal oval window morphology ( J:50488 )

• the oval window is displaced medially

absent Meckel's cartilage ( J:50488 )

• most of Meckel's cartilage is absent; only the distal tip and a small proximal part is present

absent temporal bone squamous part ( J:50488 )

absent zygomatic arch ( J:50488 )

• the entire zygomatic arch is absent

abnormal hyoid bone morphology ( J:50488 )

• the styloid process is abnormally fused to the hyoid bone

absent incisors ( J:50488 )

• mandibular incisors are either absent (38%) or a single median incisor is observed (42%)

• in contrast, molars appear unaffected

• in some cases, a rudimentary second incisor is observed (12%)

abnormal mandible morphology ( J:50488 )

• at E18.5, ~8% of double homozygotes show a cleft mandible and tongue

• dentaries are shortened and their distal tips fused

short mandible ( J:50488 )

• at E12.5, the lower jaw is much shorter than normal

absent maxillary shelf ( J:50488 )

absent maxillary zygomatic process ( J:50488 )

• the malar (zygomatic) process of the maxilla is absent

micrognathia ( J:50488 )

• severely reduced lower jaw

absent zygomatic bone ( J:50488 )

abnormal malleus morphology ( J:50488 )

• malformed malleus, with an ectopic process immediately distal from the malleus

abnormal stapes morphology ( J:50488 )

• the stylohyoid ligament is chondrified and connects the stapes and the styloid process to the lesser horn of the hyoid bone; as a result, the stapes is displaced

cleft secondary palate ( J:50488 )

abnormal tongue position ( J:50488 )

• tongue inserts through the cleft palate into the nasal cavity, obstructing the airway

pointed snout ( J:50488 )

anotia ( J:50488 )

• absence of external ears

• an ectopic crescent-shaped cartilaginous element is found in the remnant of the auricle

hearing/vestibular/ear

abnormal oval window morphology ( J:50488 )

• the oval window is displaced medially

abnormal malleus morphology ( J:50488 )

• malformed malleus, with an ectopic process immediately distal from the malleus

abnormal stapes morphology ( J:50488 )

• the stylohyoid ligament is chondrified and connects the stapes and the styloid process to the lesser horn of the hyoid bone; as a result, the stapes is displaced

anotia ( J:50488 )

• absence of external ears

• an ectopic crescent-shaped cartilaginous element is found in the remnant of the auricle

absent lateral semicircular canal ( J:50488 )

• only a remnant of the lateral duct found in a small cavity in the otic capsule is observed

small otic capsule ( J:50488 )

• in newborns, the entire otic capsule is reduced due to reduced outgrowth of the ducts of the membranous labyrinth

homeostasis/metabolism

cyanosis ( J:50488 )

• newborn double homozygotes are cyanotic, indicating lack of oxygen

digestive/alimentary system

absent maxillary shelf ( J:50488 )

cleft secondary palate ( J:50488 )

abnormal tongue position ( J:50488 )

• tongue inserts through the cleft palate into the nasal cavity, obstructing the airway

nervous system

spina bifida ( J:50488 )

• all double homozygotes exhibit spina bifida, as neural arches spread out laterally

embryo

spina bifida ( J:50488 )

• all double homozygotes exhibit spina bifida, as neural arches spread out laterally

growth/size/body

absent incisors ( J:50488 )

• mandibular incisors are either absent (38%) or a single median incisor is observed (42%)

• in contrast, molars appear unaffected

• in some cases, a rudimentary second incisor is observed (12%)

absent maxillary shelf ( J:50488 )

cleft secondary palate ( J:50488 )

abnormal tongue position ( J:50488 )

• tongue inserts through the cleft palate into the nasal cavity, obstructing the airway

pointed snout ( J:50488 )

anotia ( J:50488 )

• absence of external ears

• an ectopic crescent-shaped cartilaginous element is found in the remnant of the auricle

Genotype
MGI:3698248

cx3

• Allelic Composition: Prrx1^tm1Tex/Prrx1⁺; Prrx2^tm1Hubr/Prrx2^tm1Hubr
• Genetic Background: involves: 129P2/OlaHsd * 129S7/SvEvBrd * FVB

mortality/aging

neonatal lethality, incomplete penetrance ( J:50488 )

• ~80% of newborns die within 24 hrs

• surviving newborns reach adulthood and appear healthy while most of their offspring survive with no problems

respiratory system

respiratory distress ( J:50488 )

• ~80% of newborns show respiratory problems

growth/size/body

palatal shelf hypoplasia ( J:50488 )

cleft secondary palate ( J:50488 )

• ~80% of newborns display a cleft secondary palate

distended abdomen ( J:50488 )

• ~80% of newborns display abdominal distension

craniofacial

palatal shelf hypoplasia ( J:50488 )

cleft secondary palate ( J:50488 )

• ~80% of newborns display a cleft secondary palate

digestive/alimentary system

palatal shelf hypoplasia ( J:50488 )

cleft secondary palate ( J:50488 )

• ~80% of newborns display a cleft secondary palate

skeleton

abnormal stylohyoid ligament morphology ( J:50488 )

• the stylohyoid ligament is chondrified

Genotype
MGI:3698249

cx4

• Allelic Composition: Prrx1^tm1Tex/Prrx1^tm1Tex; Prrx2^tm1Hubr/Prrx2⁺
• Genetic Background: involves: 129P2/OlaHsd * 129S7/SvEvBrd * FVB

craniofacial

short Meckel's cartilage ( J:50488 )

• at E14.5, Meckel's cartilage is truncated

abnormal incisor morphology ( J:50488 )

• newborns exhibit closely spaced incisors

abnormal mandible morphology ( J:50488 )

• newborns exhibit shortened dentaries

skeleton

short Meckel's cartilage ( J:50488 )

• at E14.5, Meckel's cartilage is truncated

abnormal incisor morphology ( J:50488 )

• newborns exhibit closely spaced incisors

abnormal mandible morphology ( J:50488 )

• newborns exhibit shortened dentaries

abnormal metacarpal bone morphology ( J:50488 )

• the base of the metacarpal of the fifth digit is broader and forms an articulation with the trinagular and ulna

growth/size/body

abnormal incisor morphology ( J:50488 )

• newborns exhibit closely spaced incisors

limbs/digits/tail

abnormal metacarpal bone morphology ( J:50488 )

• the base of the metacarpal of the fifth digit is broader and forms an articulation with the trinagular and ulna