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Phenotypes associated with this allele
Allele Symbol
Allele Name
Allele ID
Gas1tm1Fan
targeted mutation 1, Chen-Ming Fan
MGI:2388397
Summary 5 genotypes
Jump to Allelic Composition Genetic Background Genotype ID
hm1
Gas1tm1Fan/Gas1tm1Fan involves: 129S1/Sv * 129X1/SvJ * C57BL/6 MGI:3640834
hm2
Gas1tm1Fan/Gas1tm1Fan involves: 129S1/Sv * 129X1/SvJ * CD-1 MGI:3640836
cx3
Gas1tm1Fan/Gas1tm1Fan
Shhtm1Chg/Shh+
involves: 129S1/Sv * 129X1/SvJ * C57BL/6 MGI:7386875
cx4
Gas1tm1Fan/Gas1tm1Fan
Shhtm1Chg/Shhtm1Chg
involves: 129S1/Sv * 129X1/SvJ * C57BL/6 MGI:7386876
cx5
Gas1tm1Fan/Gas1tm1Fan
Vax1tm1Pgr/Vax1tm1Pgr
involves: 129S1/Sv * 129X1/SvJ * C57BL/6 MGI:7387091


Genotype
MGI:3640834
hm1
Allelic
Composition
Gas1tm1Fan/Gas1tm1Fan
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gas1tm1Fan mutation (0 available); any Gas1 mutation (14 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
• Background Sensitivity: on background involving C57BL/6 in addition to 129, most mice die within 3 days of birth and very few live to 3 weeks of age

craniofacial
• at P0, mice exhibit chondrocranial (including both neurocranial and splanchnocranial) and dermatocranial defects esp. along the neurocranial midline and in the middle and inner ear, but including all three primary sensory capsules (nasal, optic, and otic)
• midline defects vary in severity, ranging from bilateral cleft of the secondary palate to absence of elaborated premaxillary palatal processes or failure of the maxillary and palatine palatal processes to fuse in the midline
• at P0, 67% of mice exhibit a large midline basicranial hypophyseal fenestration in the basisphenoid
• hypoglossal foramen is absent
• styloid process is typically markedly hypoplastic and separated into tympanohyal and stylohyal portions
• ala temporali are reduced in size
• retroarticular processes of the squamosals are dysmorphic
• at P0, 40% of mice exhibit fusion of the premaxillary incisors; instead of two separate tooth germs located adjacent to the nasal cavity, a fused incisor crown is found below the nasal septum in the midline
• at P0, 50% of mice exhibit variable premaxilla synostosis across the midline along with a single premaxillary incisor crown within the premaxillae
• at P0, the premaxillae are hypoplastic
• malleus lacks a normal neck, manubrium, and processus brevis and is sometimes synchondrotic with the remnant of the incus
• in some cases, gonial bones are absent
• when present, gonial bones are hypoplastic
• stapes is not entirely normal and is occasionally synchondrotic with the otic capsule
• nasal capsular cartilages show midline defects, including absence of elaborated paraseptal cartilages
• however, the external nares are patent
• BrdU analysis of E13.5 palatal shelves showed significantly reduced cell proliferation rates in the palate mesenchyme of the middle and posterior apex and bend
• at E13.5, palatal shelves show reduced Ptc1 expression that fails to extend along their length and is lost in the palatal bend mesenchyme
• BrdU analysis of E13.5 palatal shelves showed significantly reduced cell proliferation rates in the palate epithelium of the middle and posterior apex and in the palate mesenchyme of the middle and posterior apex and bend
• although palatal shelves elevate above the tongue and orient into a horizontal position, they fail to contact each other and fuse in the midline at E15.5
• at P0, 30% of mice exhibit complete secondary cleft palate while an additional 30% show partial secondary cleft palate
• at E12.5, the vomeronasal organ surrounded by the early paraseptal cartilage fails to develop
• at P0, the external auditory meatus is hypoplastic or nearly absent

vision/eye
• eye abnormalities apparent as early as E11.5 and persistent through E12.5 and E14.5
• fails to form ventrally
• iris fails to form ventrally
• smaller, thicker
• lens either small or absent
• detached from ventral neuroepithelium
• eyes tilted ventrally (J:70735)
• after day 5, structures of the eye are difficult to distinguish (J:70735)
• at P0, the ala hypochiasmatica and associated optic pillars of the optic capsules are missing (J:122159)
• eyelids much closer together
• little or no retinal pigment epithelium
• ventral retinal pigment layer shows increased cell proliferation around E10.5 and takes on characteristics of the neuroretina
• disorganized neural retina
• ventral neural retina curves outward to become multilayered
• minimal ganglion layer persists through E18.5
• no vitreous humour

digestive/alimentary system
• BrdU analysis of E13.5 palatal shelves showed significantly reduced cell proliferation rates in the palate mesenchyme of the middle and posterior apex and bend
• at E13.5, palatal shelves show reduced Ptc1 expression that fails to extend along their length and is lost in the palatal bend mesenchyme
• BrdU analysis of E13.5 palatal shelves showed significantly reduced cell proliferation rates in the palate epithelium of the middle and posterior apex and in the palate mesenchyme of the middle and posterior apex and bend
• although palatal shelves elevate above the tongue and orient into a horizontal position, they fail to contact each other and fuse in the midline at E15.5
• at P0, 30% of mice exhibit complete secondary cleft palate while an additional 30% show partial secondary cleft palate

pigmentation
• little or no retinal pigment epithelium
• ventral retinal pigment layer shows increased cell proliferation around E10.5 and takes on characteristics of the neuroretina

growth/size/body
• at P0, 40% of mice exhibit fusion of the premaxillary incisors; instead of two separate tooth germs located adjacent to the nasal cavity, a fused incisor crown is found below the nasal septum in the midline
• nasal capsular cartilages show midline defects, including absence of elaborated paraseptal cartilages
• however, the external nares are patent
• BrdU analysis of E13.5 palatal shelves showed significantly reduced cell proliferation rates in the palate mesenchyme of the middle and posterior apex and bend
• at E13.5, palatal shelves show reduced Ptc1 expression that fails to extend along their length and is lost in the palatal bend mesenchyme
• BrdU analysis of E13.5 palatal shelves showed significantly reduced cell proliferation rates in the palate epithelium of the middle and posterior apex and in the palate mesenchyme of the middle and posterior apex and bend
• although palatal shelves elevate above the tongue and orient into a horizontal position, they fail to contact each other and fuse in the midline at E15.5
• at P0, 30% of mice exhibit complete secondary cleft palate while an additional 30% show partial secondary cleft palate
• at E12.5, the vomeronasal organ surrounded by the early paraseptal cartilage fails to develop
• at P0, the external auditory meatus is hypoplastic or nearly absent

hearing/vestibular/ear
• malleus lacks a normal neck, manubrium, and processus brevis and is sometimes synchondrotic with the remnant of the incus
• in some cases, gonial bones are absent
• when present, gonial bones are hypoplastic
• stapes is not entirely normal and is occasionally synchondrotic with the otic capsule
• at P0, the external auditory meatus is hypoplastic or nearly absent
• otic capsule is dysmorphic
• tegmen tympani is dysmorphic
• at P0, tympanic rings show variable size and shape, but are usually much smaller in diameter and thicker

nervous system
• at E12.5, the vomeronasal organ surrounded by the early paraseptal cartilage fails to develop
• mice show microform holoprosencephaly, including midfacial hypoplasia, premaxillary incisor fusion, and cleft palate as well severe ear defects
• however, the forebrain remains grossly intact

respiratory system
• nasal capsular cartilages show midline defects, including absence of elaborated paraseptal cartilages
• however, the external nares are patent
• at E12.5, the vomeronasal organ surrounded by the early paraseptal cartilage fails to develop

skeleton
• at P0, mice exhibit chondrocranial (including both neurocranial and splanchnocranial) and dermatocranial defects esp. along the neurocranial midline and in the middle and inner ear, but including all three primary sensory capsules (nasal, optic, and otic)
• midline defects vary in severity, ranging from bilateral cleft of the secondary palate to absence of elaborated premaxillary palatal processes or failure of the maxillary and palatine palatal processes to fuse in the midline
• at P0, 67% of mice exhibit a large midline basicranial hypophyseal fenestration in the basisphenoid
• hypoglossal foramen is absent
• styloid process is typically markedly hypoplastic and separated into tympanohyal and stylohyal portions
• ala temporali are reduced in size
• retroarticular processes of the squamosals are dysmorphic
• at P0, 40% of mice exhibit fusion of the premaxillary incisors; instead of two separate tooth germs located adjacent to the nasal cavity, a fused incisor crown is found below the nasal septum in the midline
• at P0, 50% of mice exhibit variable premaxilla synostosis across the midline along with a single premaxillary incisor crown within the premaxillae
• at P0, the premaxillae are hypoplastic
• malleus lacks a normal neck, manubrium, and processus brevis and is sometimes synchondrotic with the remnant of the incus
• in some cases, gonial bones are absent
• when present, gonial bones are hypoplastic
• stapes is not entirely normal and is occasionally synchondrotic with the otic capsule
• nasal capsular cartilages show midline defects, including absence of elaborated paraseptal cartilages
• however, the external nares are patent
• malleus is sometimes synchondrotic with the remnant of the incus
• a process extending from either the incus or the malleus portion of the fused elements is often synchondrotically fused with the stapes
• stapes is occasionally synchondrotic with the otic capsule
• at P0, 50% of mice exhibit variable premaxilla synostosis across the midline




Genotype
MGI:3640836
hm2
Allelic
Composition
Gas1tm1Fan/Gas1tm1Fan
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ * CD-1
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gas1tm1Fan mutation (0 available); any Gas1 mutation (14 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
N
• Background Sensitivity: homozygous mice are viable to adulthood on a genetic background involving CD-1 (J:70736)
(J:79482)

vision/eye

nervous system
• somewhat shallow foliation at 2 days of age
• smaller folia
• reduced cell proliferation
• increased apoptosis
• basket cells are more densely distributed with a smaller wrapping area
• reduced cell proliferation
• cell bodies are smaller and more densely distributed
• abnormalities develop gradually and relatively late
• dendritic trees are less organized and elaborated, particularly near the pia surface
• area in section only about 47% of controls
• radial fiber abnormalities develop early
• reduced in number and morphologically immature
• normal in size at 2 days of age
• growth retardation after 2 days and visibly smaller than controls at 30 days of age when mass is half that of controls
• uvular sulcus absent

behavior/neurological
• wobbling and halting gait
• no overt ataxia

limbs/digits/tail
• reduced apoptosis in limbs
• apical ectodermal ridge is thinner than normal
• mesenchymal mass of limbs reduced by E11.5
• smaller fore- and hind-paws at birth
• paws nearly normal in size in adults
• disproportionate reduction of digits I to III
• soft tissue fusions between digits II and III
• second phalange of digit II is sometimes absent
• calcified regions are normal but chondrogenic regions are reduced
• reduced in size
• calcified regions are normal but chondrogenic regions are reduced
• reduced in size
• calcified regions are normal but chondrogenic regions are reduced
• delayed digit formation

skeleton
• second phalange of digit II is sometimes absent
• calcified regions are normal but chondrogenic regions are reduced
• reduced in size
• calcified regions are normal but chondrogenic regions are reduced
• reduced in size
• calcified regions are normal but chondrogenic regions are reduced

pigmentation

embryo
• reduced apoptosis in limbs
• apical ectodermal ridge is thinner than normal
• mesenchymal mass of limbs reduced by E11.5




Genotype
MGI:7386875
cx3
Allelic
Composition
Gas1tm1Fan/Gas1tm1Fan
Shhtm1Chg/Shh+
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gas1tm1Fan mutation (0 available); any Gas1 mutation (14 available)
Shhtm1Chg mutation (2 available); any Shh mutation (48 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging

craniofacial
• perinatal skulls show exacerbated neurocranial, splanchnocranial, and dermatocranial defects relative to the single Gas1tm1Fan homozygotes
• midline craniofacial phenotype is significantly worsened relative to that in single Gas1tm1Fan homozygotes
• Meckels cartilage is truncated and lacks a malleal end; the proximal end is slightly bifurcated
• perinatal skull size is reduced
• neurocranial base development is severely disrupted: the trabecular basal plate, which runs from the rostral basisphenoid, presphenoid, and ethmoid through the nasal septum, is discontinuous and cleft
• all lateral extensions from the neurocranial base are disrupted: the ala temporali are hypoplastic, the lamina obturans fail to invest the cartilage of the ala, and ectopic preotic cartilaginous pillars extend toward the crista parotica of the otic capsule
• at E18.5, 75% of mice exhibit clefting of the basisphenoid
• the ala temporali are hypoplastic
• squamosal bones are repatterned and separated into distinct retrotympanic and squamosal portions
• at E18.5, 25% of mice show fusion of the premaxillary incisors, 75% of mice show premaxillary incisor agenesis, and 75% show fusion of the mandibular incisors
• at E18.5, the distal dentary contains a single lower incisor
• at E18.5, the duplicated proximal dentary includes an alveolus containing an ectopic molar
• at E18.5, the proximal dentary appears to be duplicated and includes a secondary cartilage-containing condylar process and an alveolus containing an ectopic molar
• the distal dentary is synostotic across the midline and contains a single lower incisor
• at E18.5, the distal dentary lacks a symphysis as it is synostotic across the midline; 75% of mice exhibit a synostotic mandible/symphysis phenotype
• at E18.5, premaxillaries are hypoplastic, synostotic, and lack incisor teeth
• gonial bones fail to form
• a vestigial stapes is observed
• nasal capsules and associated dermal ossifications are severely reduced, without proper midline manifestations
• at E18.5, all (100%) of mice exhibit complete secondary cleft palate
• mice survive to birth but only have a single external nostril

growth/size/body
• at E18.5, 25% of mice show fusion of the premaxillary incisors, 75% of mice show premaxillary incisor agenesis, and 75% show fusion of the mandibular incisors
• at E18.5, the distal dentary contains a single lower incisor
• at E18.5, the duplicated proximal dentary includes an alveolus containing an ectopic molar
• nasal capsules and associated dermal ossifications are severely reduced, without proper midline manifestations
• at E18.5, all (100%) of mice exhibit complete secondary cleft palate
• mice survive to birth but only have a single external nostril

nervous system
• mice exhibit a more severe holoprosencephaly phenotype than single Gas1tm1Fan homozygotes

respiratory system
• nasal capsules and associated dermal ossifications are severely reduced, without proper midline manifestations
• mice survive to birth but only have a single external nostril

skeleton
• perinatal skulls show exacerbated neurocranial, splanchnocranial, and dermatocranial defects relative to the single Gas1tm1Fan homozygotes
• midline craniofacial phenotype is significantly worsened relative to that in single Gas1tm1Fan homozygotes
• Meckels cartilage is truncated and lacks a malleal end; the proximal end is slightly bifurcated
• perinatal skull size is reduced
• neurocranial base development is severely disrupted: the trabecular basal plate, which runs from the rostral basisphenoid, presphenoid, and ethmoid through the nasal septum, is discontinuous and cleft
• all lateral extensions from the neurocranial base are disrupted: the ala temporali are hypoplastic, the lamina obturans fail to invest the cartilage of the ala, and ectopic preotic cartilaginous pillars extend toward the crista parotica of the otic capsule
• at E18.5, 75% of mice exhibit clefting of the basisphenoid
• the ala temporali are hypoplastic
• squamosal bones are repatterned and separated into distinct retrotympanic and squamosal portions
• at E18.5, 25% of mice show fusion of the premaxillary incisors, 75% of mice show premaxillary incisor agenesis, and 75% show fusion of the mandibular incisors
• at E18.5, the distal dentary contains a single lower incisor
• at E18.5, the duplicated proximal dentary includes an alveolus containing an ectopic molar
• at E18.5, the proximal dentary appears to be duplicated and includes a secondary cartilage-containing condylar process and an alveolus containing an ectopic molar
• the distal dentary is synostotic across the midline and contains a single lower incisor
• at E18.5, the distal dentary lacks a symphysis as it is synostotic across the midline; 75% of mice exhibit a synostotic mandible/symphysis phenotype
• at E18.5, premaxillaries are hypoplastic, synostotic, and lack incisor teeth
• gonial bones fail to form
• a vestigial stapes is observed
• nasal capsules and associated dermal ossifications are severely reduced, without proper midline manifestations
• at E18.5, 100% of premaxillaries are synostotic
• no patent sutures between the frontal and parietal ossifications are observed

hearing/vestibular/ear
• middle ear-associated splanchnocranial elements either fail to develop (malleus and incus) or are represented by a cartilaginous remnant (stapes)
• dermatocranial elements (ectotympanic and gonial bones) fail to form
• gonial bones fail to form
• a vestigial stapes is observed
• ectotympanic bones fail to form

digestive/alimentary system
• at E18.5, all (100%) of mice exhibit complete secondary cleft palate




Genotype
MGI:7386876
cx4
Allelic
Composition
Gas1tm1Fan/Gas1tm1Fan
Shhtm1Chg/Shhtm1Chg
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gas1tm1Fan mutation (0 available); any Gas1 mutation (14 available)
Shhtm1Chg mutation (2 available); any Shh mutation (48 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
mortality/aging
• mice only survive to around E9.5

craniofacial
• mice exhibit severe craniofacial defects




Genotype
MGI:7387091
cx5
Allelic
Composition
Gas1tm1Fan/Gas1tm1Fan
Vax1tm1Pgr/Vax1tm1Pgr
Genetic
Background
involves: 129S1/Sv * 129X1/SvJ * C57BL/6
Find Mice Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Gas1tm1Fan mutation (0 available); any Gas1 mutation (14 available)
Vax1tm1Pgr mutation (1 available); any Vax1 mutation (14 available)
phenotype observed in females
phenotype observed in males
N normal phenotype
craniofacial
• at E15.5, double homozygotes show a complete absence of maxillary incisors, unlike single homozygotes which exhibit a single median maxillary central incisor (SMMCI)
• however, normal bilateral external nares and an intact upper lip are present, and no cleft palate is observed

growth/size/body
• at E15.5, double homozygotes show a complete absence of maxillary incisors, unlike single homozygotes which exhibit a single median maxillary central incisor (SMMCI)
• however, normal bilateral external nares and an intact upper lip are present, and no cleft palate is observed

skeleton
• at E15.5, double homozygotes show a complete absence of maxillary incisors, unlike single homozygotes which exhibit a single median maxillary central incisor (SMMCI)
• however, normal bilateral external nares and an intact upper lip are present, and no cleft palate is observed





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last database update
11/12/2024
MGI 6.24
The Jackson Laboratory