Phenotypes associated with this allele

• Allele Symbol: Mef2c^tm1Eno
• Allele Name: targeted mutation 1, Eric N Olson
• Allele ID: MGI:1857491
• Summary: 13 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Mef2c^tm1Eno/Mef2c^tm1Eno	involves: 129S7/SvEvBrd	MGI:3578807
hm2	Mef2c^tm1Eno/Mef2c^tm1Eno	involves: 129S7/SvEvBrd * C57BL/6	MGI:2166806
ht3	Mef2c^tm1Eno/Mef2c^+	involves: 129S7/SvEvBrd	MGI:3719006
cn4	Mef2c^tm1Eno/Mef2c^tm1Jjs Myl2^tm1(cre)Krc/Myl2^+	involves: 129S4/SvJae * 129S6/SvEvTac * 129S7/SvEvBrd	MGI:3613581
cn5	Gt(ROSA)26Sor^tm1Sor/Gt(ROSA)26Sor^+ Mef2c^tm1Eno/Mef2c^tm1Jjs H2az2^Tg(Wnt1-cre)11Rth/H2az2^+	involves: 129S4/SvJaeSor * 129S6/SvEvTac * 129S7/SvEvBrd * C57BL/6J * CBA/J	MGI:6209743
cn6	Mef2c^tm1Eno/Mef2c^tm1Jjs Tg(Myh6-cre)2182Mds/0	involves: 129S4/SvJaeSor * 129S6/SvEvTac * 129S7/SvEvBrd * FVB/N	MGI:3613580
cn7	Mef2c^tm1Eno/Mef2c^tm1Jjs H2az2^Tg(Wnt1-cre)11Rth/H2az2^+	involves: 129S6/SvEvTac * 129S7/SvEvBrd * C57BL/6J * CBA/J	MGI:6209712
cn8	Mef2c^tm1Eno/Mef2c^tm2Eno Tg(Myog-cre)1Eno/0	involves: 129S/SvEv * 129S7/SvEvBrd	MGI:4418148
cn9	Mef2c^tm1Eno/Mef2c^tm2Eno Twist2^tm1(cre)Dor/Twist2^+	involves: 129S/SvEv * 129S7/SvEvBrd * 129X1/SvJ	MGI:3719010
cn10	Mef2c^tm1Eno/Mef2c^tm2Eno Tg(Col2a1-cre)1Bhr/0	involves: 129S/SvEv * 129S7/SvEvBrd * C57BL/6 * SJL	MGI:3719016
cx11	Hdac4^tm1Eno/Hdac4^tm1Eno Mef2c^tm1Eno/Mef2c^+	involves: 129S7/SvEvBrd	MGI:3719020
cx12	Del(6Dlx6-Dlx5)1Tlu/+ Mef2c^tm1Eno/Mef2c^+	involves: 129S7/SvEvBrd	MGI:6209777
cx13	Mef2c^tm1Eno/Mef2c^+ Mef2d^tm1.1Eno/Mef2d^+	involves: 129S7/SvEvBrd	MGI:3719007

Genotype
MGI:3578807

hm1

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm1Eno
• Genetic Background: involves: 129S7/SvEvBrd

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

mortality/aging

embryonic lethality during organogenesis, complete penetrance ( J:40724 )

• frequency of homozygous embryos normal up to E9.5

• no viable mutants by E10.5

embryo

abnormal vitelline vasculature morphology ( J:56426 )

• vitelline vein and artery are present but with little or no blood

embryonic growth retardation ( J:40724 )

• growth normal until E9.0

• growth retarded after E9.0

incomplete somite formation ( J:40724 )

• development up to 14 somite stage (E9.0)

• never more than 20 somites formed

cardiovascular system

abnormal cardiovascular system morphology ( J:40724 )

abnormal blood vessel morphology ( J:56426 )

• less branching than normal

• cranial and caudal blood vessels are dilated

• vessels dorsal and rostral to the heart are narrow and sometimes discontinuous

abnormal vitelline vasculature morphology ( J:56426 )

• vitelline vein and artery are present but with little or no blood

abnormal heart development ( J:40724 )

failure of heart looping ( J:40724 )

• heart normal at E8.0-8.25 (linear heart tube)

• looping to the right did not occur

abnormal sinus venosus morphology ( J:40724 )

• sinus venosus frequently not present

ventricular hypoplasia ( J:40724 )

trabecula carnea hypoplasia ( J:40724 )

• lumen of ventricle very narrow

decreased cardiac muscle contractility ( J:40724 )

• contractions initiated but slow and irregular (26 beats/minute as opposed to 58 beats)

• weak atrial chamber beating

decreased ventricle muscle contractility ( J:40724 )

• only vibrates in response to atrium, no independent contractions

hematopoietic system

abnormal definitive hematopoiesis ( J:56426 )

• less blood than normal is present

growth/size/body

embryonic growth retardation ( J:40724 )

• growth normal until E9.0

• growth retarded after E9.0

muscle

trabecula carnea hypoplasia ( J:40724 )

• lumen of ventricle very narrow

decreased cardiac muscle contractility ( J:40724 )

• contractions initiated but slow and irregular (26 beats/minute as opposed to 58 beats)

• weak atrial chamber beating

decreased ventricle muscle contractility ( J:40724 )

• only vibrates in response to atrium, no independent contractions

Genotype
MGI:2166806

hm2

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm1Eno
• Genetic Background: involves: 129S7/SvEvBrd * C57BL/6

cardiovascular system

abnormal vascular development ( J:50309 )

abnormal dorsal aorta morphology ( J:50309 )

• bilateral dorsal aortae fail to form

dilated dorsal aorta ( J:50309 )

• dorsal aortae seen caudally but are dilated

abnormal pharyngeal arch artery morphology ( J:50309 )

• traces of branchial arch arteries are detectable, but they are abnormal, lack integrity and have thin walls

abnormal vascular endothelial cell development ( J:50309 )

• endothelial cells disorganized and present in lower numbers

abnormal vitelline vasculature morphology ( J:50309 )

• no discrete blood vessels develop in the yolk sac

• red blood cells are detectable however

abnormal endocardium morphology ( J:50309 )

• endocardium present but disorganized

thin ventricular wall ( J:50309 )

embryo

abnormal pharyngeal arch artery morphology ( J:50309 )

• traces of branchial arch arteries are detectable, but they are abnormal, lack integrity and have thin walls

abnormal vitelline vasculature morphology ( J:50309 )

• no discrete blood vessels develop in the yolk sac

• red blood cells are detectable however

craniofacial

abnormal pharyngeal arch artery morphology ( J:50309 )

• traces of branchial arch arteries are detectable, but they are abnormal, lack integrity and have thin walls

Genotype
MGI:3719006

ht3

• Allelic Composition: Mef2c^tm1Eno/Mef2c⁺
• Genetic Background: involves: 129S7/SvEvBrd

mortality/aging

mortality/aging ( J:122483 )

N • heterozygotes appear normal at birth and generally survive to weaning; only 1 of 18 mice born is scored as dead or clearly cyanotic and dying, indicating that neonatal viability is not significantly affected relative to wild-type controls

skeleton

failure of sternum ossification ( J:119152 )

• lack ossification within the sternum at P1 and the sternebrae and xiphoid processes remain cartilaginous; sternum shows almost complete absence of trabeculated bone

Genotype
MGI:3613581

cn4

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm1Jjs; Myl2^tm1(cre)Krc/Myl2⁺
• Genetic Background: involves: 129S4/SvJae * 129S6/SvEvTac * 129S7/SvEvBrd

normal phenotype

no abnormal phenotype detected ( J:100949 )

• no defects in heart or body weight parameters or in electrocardiogram analyses are seen in mice between 14 and 40 weeks of age

• suggests that this gene is not required for development or function of the heart after the looping morphogenesis stage

Genotype
MGI:6209743

cn5

• Allelic Composition: Gt(ROSA)26Sor^tm1Sor/Gt(ROSA)26Sor⁺; Mef2c^tm1Eno/Mef2c^tm1Jjs; H2az2^{Tg(Wnt1-cre)11Rth}/H2az2⁺
• Genetic Background: involves: 129S4/SvJaeSor * 129S6/SvEvTac * 129S7/SvEvBrd * C57BL/6J * CBA/J

embryo

embryo phenotype ( J:122483 )

N • X-Gal staining of E9.5 embryos showed no obvious defects in neural crest contribution to the branchial arches or craniofacial mesenchyme relative to control embryos

Genotype
MGI:3613580

cn6

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm1Jjs; Tg(Myh6-cre)2182Mds/0
• Genetic Background: involves: 129S4/SvJaeSor * 129S6/SvEvTac * 129S7/SvEvBrd * FVB/N

normal phenotype

no abnormal phenotype detected ( J:100949 )

• no defects in heart or body weight parameters or in electrocardiogram analyses are seen in mice between 14 and 40 weeks of age

• suggests that this gene is not required for development or function of the heart after the looping morphogenesis stage

Genotype
MGI:6209712

cn7

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm1Jjs; H2az2^{Tg(Wnt1-cre)11Rth}/H2az2⁺
• Genetic Background: involves: 129S6/SvEvTac * 129S7/SvEvBrd * C57BL/6J * CBA/J

mortality/aging

neonatal lethality, complete penetrance ( J:122483 )

• mice are born at normal ratios and are responsive to touch; however, all mice die from asphyxiation caused by upper airway obstruction within an hr of birth

• tracheostomy results in recovery from cyanosis and restoration of viability prior to humane euthanasia

homeostasis/metabolism

cyanosis ( J:122483 )

• mice become cyanotic soon after birth

respiratory system

abnormal respiratory system morphology ( J:122483 )

• at P0, the upper airway is constricted/obstructed, unlike in control mice

craniofacial

temporal bone hypoplasia ( J:122483 )

zygomatic arch hypoplasia ( J:122483 )

abnormal mandibular angle morphology ( J:122483 )

• at P0, the angular processes of the mandibles are severely hypoplastic

mandibular condyloid process hypoplasia ( J:122483 )

• at P0, the condular processes of the mandibles are severely hypoplastic

mandibular coronoid process hypoplasia ( J:122483 )

• at P0, the coronoid processes of the mandibles are severely hypoplastic

mandible hypoplasia ( J:122483 )

short mandible ( J:122483 )

• at P0, the mandible is markedly shorter

abnormal craniofacial development ( J:122483 )

• neonatal skulls display several defective or missing craniofacial structures

• defects in craniofacial development are observed as early as E13.5

• however, no obvious changes are observed in proliferation or apoptosis at E9.5 or E10.5

Meckel's cartilage hypoplasia ( J:122483 )

• at E16.5, embryos exhibit a hypoplastic Meckels cartilage; hypoplasia is already evident at E13.5, i.e. prior to the onset of ossification

abnormal pharyngeal arch morphology ( J:122483 )

• at E9.5, expression of Dlx5, Dlx6, and Hand2 is almost completely absent in the first and second branchial arches relative to control embryos

• however, Prx1 expression is normal, indicating that overall branchial arch development is not defective at E9.5

cleft palate ( J:122483 )

• all newborns exhibit a posterior cleft of the palate

glossoptosis ( J:122483 )

• all newborns exhibit defective positioning of the tongue near the back of the oral cavity, unlike control mice

skeleton

Meckel's cartilage hypoplasia ( J:122483 )

• at E16.5, embryos exhibit a hypoplastic Meckels cartilage; hypoplasia is already evident at E13.5, i.e. prior to the onset of ossification

temporal bone hypoplasia ( J:122483 )

zygomatic arch hypoplasia ( J:122483 )

abnormal mandibular angle morphology ( J:122483 )

• at P0, the angular processes of the mandibles are severely hypoplastic

mandibular condyloid process hypoplasia ( J:122483 )

• at P0, the condular processes of the mandibles are severely hypoplastic

mandibular coronoid process hypoplasia ( J:122483 )

• at P0, the coronoid processes of the mandibles are severely hypoplastic

mandible hypoplasia ( J:122483 )

short mandible ( J:122483 )

• at P0, the mandible is markedly shorter

delayed bone ossification ( J:122483 )

• at E16.5, embryos exhibit a hypoplastic Meckels cartilage and delayed ossification in the mandible and maxilla relative to control mice

growth/size/body

abnormal head morphology ( J:122483 )

• all newborns exhibit misshapen heads

cleft palate ( J:122483 )

• all newborns exhibit a posterior cleft of the palate

glossoptosis ( J:122483 )

• all newborns exhibit defective positioning of the tongue near the back of the oral cavity, unlike control mice

pigmentation

abnormal melanocyte differentiation ( J:173609 )

• embryos show reduced expression of the melanocyte markers Pmel17, Mitf and Dct in multiple regions during embryonic/fetal development

abnormal dermal melanocyte morphology ( J:173609 )

• newborn mice show a significant reduction in the number of DOPA-stained follicular and interfollicular melanocytes in the dermis relative to control mice

• few remaining dermal melanocytes have significantly fewer melanosomes than melanocytes in control mice

abnormal epidermal melanocyte morphology ( J:173609 )

• newborn mice exhibit significantly fewer DOPA-stained follicular melanocytes in the epidermis than control mice

decreased skin pigmentation ( J:173609 )

• mice exhibit significant loss of pigmentation at birth

decreased melanocyte number ( J:173609 )

• DOPA staining of neonatal skin tissue shows a significant reduction in the number of melanocytes in epidermis and dermis relative to control mice

• in neonatal epidermis, the number of DOPA-stained melanocytes is reduced by 87% relative to control mice

• at E12.5, embryos show only 69% as many Dct-labeled melanocytes in the interlimb region as control embryos

• however, no differences in TUNEL staining or in BrdU incorporation are noted from E11.5 to E18.5

abnormal melanosome morphology ( J:173609 )

• newborn mice exhibit a 65% reduction in the number of melanosomes in dermal melanocytes relative to control mice

integument

abnormal dermal melanocyte morphology ( J:173609 )

• newborn mice show a significant reduction in the number of DOPA-stained follicular and interfollicular melanocytes in the dermis relative to control mice

• few remaining dermal melanocytes have significantly fewer melanosomes than melanocytes in control mice

abnormal epidermal melanocyte morphology ( J:173609 )

• newborn mice exhibit significantly fewer DOPA-stained follicular melanocytes in the epidermis than control mice

decreased skin pigmentation ( J:173609 )

• mice exhibit significant loss of pigmentation at birth

hearing/vestibular/ear

absent tympanic ring ( J:122483 )

digestive/alimentary system

cleft palate ( J:122483 )

• all newborns exhibit a posterior cleft of the palate

glossoptosis ( J:122483 )

• all newborns exhibit defective positioning of the tongue near the back of the oral cavity, unlike control mice

cellular

abnormal melanocyte differentiation ( J:173609 )

• embryos show reduced expression of the melanocyte markers Pmel17, Mitf and Dct in multiple regions during embryonic/fetal development

embryo

abnormal pharyngeal arch morphology ( J:122483 )

• at E9.5, expression of Dlx5, Dlx6, and Hand2 is almost completely absent in the first and second branchial arches relative to control embryos

• however, Prx1 expression is normal, indicating that overall branchial arch development is not defective at E9.5

nervous system

nervous system phenotype ( J:173609 )

N • no obvious defects in peripheral or enteric innervation are detected at birth

Genotype
MGI:4418148

cn8

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm2Eno; Tg(Myog-cre)1Eno/0
• Genetic Background: involves: 129S/SvEv * 129S7/SvEvBrd

muscle

abnormal skeletal muscle fiber type ratio ( J:127416 )

• reduction in slow fibers within the soleus

• loss of type I fibers in the gastrocnemius and plantaris muscles and a decrease in number and intensity of type I fibers in the soleus

Genotype
MGI:3719010

cn9

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm2Eno; Twist2^tm1(cre)Dor/Twist2⁺
• Genetic Background: involves: 129S/SvEv * 129S7/SvEvBrd * 129X1/SvJ

mortality/aging

postnatal lethality, complete penetrance ( J:119152 )

• none survive beyond the first week of life

respiratory system

respiratory distress ( J:119152 )

• some mutants have difficulty breathing, evidenced by gasping and accumulation of air in the intestines

skeleton

short fibula ( J:119152 )

• truncation of the fibula is severe

short tibia ( J:119152 )

• truncation of the tibia is severe

abnormal trabecular bone morphology ( J:119152 )

• sternum and radius show completely absence of trabeculated bone

abnormal endochondral bone ossification ( J:119152 )

• mutants exhibit severe defects in ossification on nearly all endochondral bones, especially in the sternum

• ossification of the bone collar appears disorganized

• defects in endochondral ossification result from a failure of chondrocyte hypertrophy

failure of endochondral bone ossification ( J:119152 )

• vertebral bodies and the supraoccipital bone fail to ossify and many phalangeal bones of the digits lack ossification

limbs/digits/tail

short fibula ( J:119152 )

• truncation of the fibula is severe

short tibia ( J:119152 )

• truncation of the tibia is severe

short limbs ( J:119152 )

Genotype
MGI:3719016

cn10

• Allelic Composition: Mef2c^tm1Eno/Mef2c^tm2Eno; Tg(Col2a1-cre)1Bhr/0
• Genetic Background: involves: 129S/SvEv * 129S7/SvEvBrd * C57BL/6 * SJL

skeleton

decreased length of long bones ( J:119152 )

• truncation of all long bones of the limbs

abnormal endochondral bone ossification ( J:119152 )

• structures of the distal ribs, radii, and sternabrae are distorted by disorganized cartilaginous remnants of the growth plate and aberrant ossification

failure of sternum ossification ( J:119152 )

• absence of ossification of the sternum and a failure in chondrocyte hypertrophy

behavior/neurological

abnormal gait ( J:119152 )

• waddling gait due to shortened limbs

limbs/digits/tail

short limbs ( J:119152 )

• truncation of all long bones of the limbs

Genotype
MGI:3719020

cx11

• Allelic Composition: Hdac4^tm1Eno/Hdac4^tm1Eno; Mef2c^tm1Eno/Mef2c⁺
• Genetic Background: involves: 129S7/SvEvBrd

skeleton

skeleton phenotype ( J:119152 )

N • the failure of endochondral ossification that is seen in heterozygous Mef2c mutants is rescued

Genotype
MGI:6209777

cx12

• Allelic Composition: Del(6Dlx6-Dlx5)1Tlu/+; Mef2c^tm1Eno/Mef2c⁺
• Genetic Background: involves: 129S7/SvEvBrd

mortality/aging

neonatal lethality, complete penetrance ( J:122483 )

• all (9 of 9) double heterozygous mice are clearly cyanotic at birth and die on postnatal day 0 (P0)

craniofacial

abnormal palate development ( J:122483 )

• at P0, mice exhibit a small, misshapen, and incomplete palate

glossoptosis ( J:122483 )

• at P0, mice show an improper position of the tongue at the rear of the oral cavity

homeostasis/metabolism

cyanosis ( J:122483 )

• all mice are clearly cyanotic at birth

growth/size/body

abnormal palate development ( J:122483 )

• at P0, mice exhibit a small, misshapen, and incomplete palate

glossoptosis ( J:122483 )

• at P0, mice show an improper position of the tongue at the rear of the oral cavity

digestive/alimentary system

abnormal palate development ( J:122483 )

• at P0, mice exhibit a small, misshapen, and incomplete palate

glossoptosis ( J:122483 )

• at P0, mice show an improper position of the tongue at the rear of the oral cavity

Genotype
MGI:3719007

cx13

• Allelic Composition: Mef2c^tm1Eno/Mef2c⁺; Mef2d^tm1.1Eno/Mef2d⁺
• Genetic Background: involves: 129S7/SvEvBrd

mortality/aging

neonatal lethality, complete penetrance ( J:119152 )

• die within a day after birth

skeleton

failure of sternum ossification ( J:119152 )

• the lack of ossification in the sternum is more severe than in single Mef2c^tm1Eno heterozygotes

• exhibit almost no hypertrophic chondrocytes in the sternum