Phenotypes associated with this allele

• Allele Symbol: Sp1^tm1Phi
• Allele Name: targeted mutation 1, Sjaak Philipsen
• Allele ID: MGI:2181866
• Summary: 3 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Sp1^tm1Phi/Sp1^tm1Phi	involves: 129P2/OlaHsd	MGI:3029023
ht2	Sp1^tm1Phi/Sp1^+	involves: 129P2/OlaHsd * C57BL/6	MGI:3809035
cx3	Sp1^tm1Phi/Sp1^+ Sp3^tm1Sus/Sp3^+	involves: 129P2/OlaHsd * C57BL/6	MGI:3809034

Genotype
MGI:3029023

hm1

• Allelic Composition: Sp1^tm1Phi/Sp1^tm1Phi
• Genetic Background: involves: 129P2/OlaHsd

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

mortality/aging

embryonic lethality during organogenesis, complete penetrance ( J:40354 )

• embryos die between E10.5 and E11

embryo

decreased embryo size ( J:40354 )

• embryos appear smaller than controls

abnormal embryonic tissue morphology ( J:40354 )

• variable phenotype; some embryos develop recognizable structures such as somites, eyes and heart, but others exhibit no discernable structures and appear as an undifferentiated mass; no embryos exhibit normal gross morphology

growth/size/body

decreased embryo size ( J:40354 )

• embryos appear smaller than controls

Genotype
MGI:3809035

ht2

• Allelic Composition: Sp1^tm1Phi/Sp1⁺
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6

growth/size/body

decreased body size ( J:123073 )

• heterozygotes are viable and fertile, though slightly smaller than wild-type mice

vision/eye

anophthalmia ( J:123073 )

• newborn heterozygotes are sometimes missing one or both eyes

hematopoietic system

decreased erythroid progenitor cell number ( J:123073 )

• at E14.5, the frequency of erythroid BFU-E precursors, but not CFU-Es, is reduced in heterozygous fetal liver cultures relative to wild-type cultures

• in addition, the frequency of megakaryocyte progenitors (CFU-MKs) is reduced by 2-fold in heterozygous fetal liver cultures relative to wild-type cultures

• however, neither a reduction of enucleated red blood cells nor an increased number of nucleated primitive erythrocytes is noted in vivo at E16.5

Genotype
MGI:3809034

cx3

• Allelic Composition: Sp1^tm1Phi/Sp1⁺; Sp3^tm1Sus/Sp3⁺
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6

mortality/aging

lethality at weaning, complete penetrance ( J:123073 )

• no double heterozygotes are obtained at weaning

lethality throughout fetal growth and development, incomplete penetrance ( J:123073 )

• most double heterozygous embryos die between E16.5 and E18.5

• at E18.5, 20% of embryos are doubly heterozygous, but only one-third of them (6.7%) are alive and appear similar to Sp3^tm1Sus homozygous mutants

• at E18.5, dead embryos exhibit a swollen body shape and a diffuse pink color (41.7%), or different stages of resorption (25%)

respiratory system

abnormal lung morphology ( J:123073 )

• at E18.5, the overall tissue structure of mutant lung tissue is more compact than that of wild-type lung tissue

skeleton

abnormal cranium morphology ( J:123073 )

• at E18.5, various cranial bones are malformed

• unlike Sp3^tm1Sus homozygotes, double heterozygotes do not display a delay in the formation of the ameloblast layer of developing teeth at E18.5

abnormal phalanx morphology ( J:123073 )

• at E18.5, forelimb phalanges are malformed

abnormal bone ossification ( J:123073 )

• at E18.5, ossification in the main skull bones is incomplete and ossification centers of the paws are reduced

craniofacial

abnormal cranium morphology ( J:123073 )

• at E18.5, various cranial bones are malformed

• unlike Sp3^tm1Sus homozygotes, double heterozygotes do not display a delay in the formation of the ameloblast layer of developing teeth at E18.5

limbs/digits/tail

abnormal phalanx morphology ( J:123073 )

• at E18.5, forelimb phalanges are malformed

vision/eye

anophthalmia ( J:123073 )

• at E18.5, several viable embryos are missing one or both eyes

growth/size/body

decreased body size ( J:123073 )

• viable double heterozygous embryos are smaller than wild-type embryos

decreased fetal weight ( J:123073 )

• at E14.5, mutant body weight is only slightly reduced, but at E16.5 it is reduced to 67% of wild-type weight

• at these stages, the relative weight of mutant fetal livers and placentas, but not of other organs, is significantly reduced

hematopoietic system

abnormal erythropoiesis ( J:123073 )

• at E16.5, blood smears of peripheral blood indicate that up to 34% of mutant erythrocytes are nucleated (primitive, yolk sac-derived) relative to only about 1% in wild-type blood

• defects in erythroid development are already present at earlier stages

anemia ( J:123073 )

• at E16.5, a 4-fold reduction of enucleated red blood cells indicates anemia

• anemia is associated with impaired maturation of erythrocytes

decreased erythroid progenitor cell number ( J:123073 )

• at E14.5, the frequency of erythroid BFU-E and CFU-E precursors as well as megakaryocyte CFU-MK precursors is markedly reduced in mutant fetal liver cultures

homeostasis/metabolism

skin edema ( J:123073 )

• at E18.5, viable double heterozygotes show characteristic blood-filled distensions (edemas) on their back

• at E14.5 and E16.5, ~50% of double heterozygous embryos develop edemas along their back

liver/biliary system

abnormal liver sinusoid morphology ( J:123073 )

• at E16.5, mutant fetal liver sinusoids are virtually empty and erythrocytes are only found in the blood vessels

small liver ( J:123073 )

• mutant fetal livers are barely visible (E16.5) or smaller (E14.5) than the wild-type livers

decreased liver weight ( J:123073 )

• at E14.5 and E16.5, the relative weight of mutant fetal livers is significantly reduced

embryo

abnormal placenta morphology ( J:123073 )

• at E14.5 and E16.5, 75% of mutant placentae show a striking reversal of the curvature

decreased spongiotrophoblast cell number ( J:123073 )

• at E16.5, spongiotrophoblast cells are reduced

decreased spongiotrophoblast size ( J:123073 )

• at E14.5 and E16.5, the size of the spongiotrophoblast layer is visibly decreased

• at E16.5, trophoblast cell type marker analyses indicate that the spongiotrophoblast layer is thinner and abnormally shaped in 100% of mutant placentae

decreased trophoblast glycogen cell number ( J:123073 )

• at E16.5, trophoblast glycogen cells are reduced

abnormal placenta intervillous maternal lacunae morphology ( J:123073 )

• at E16.5, maternal blood spaces are enlarged and disorganized

disorganized placental labyrinth ( J:123073 )

• at E14.4, large portions of the labyrinth layer appear disorganized

• at E16.5, three of 4 labyrinth layers appear highly disorganized, showing clustered streaks with small nucleated cells

• although disorganized, fetal endothelial cells, pericytes, and sinusoidal trophoblast giant cells are all present

decreased placenta weight ( J:123073 )

• at E14.5 and E16.5, the relative weight of mutant placentas is only ~60% of wild-type placentas

cardiovascular system

abnormal liver sinusoid morphology ( J:123073 )

• at E16.5, mutant fetal liver sinusoids are virtually empty and erythrocytes are only found in the blood vessels

hypovolemia ( J:123073 )

• at E16.5, blood volume is significantly decreased

integument

skin edema ( J:123073 )

• at E18.5, viable double heterozygotes show characteristic blood-filled distensions (edemas) on their back

• at E14.5 and E16.5, ~50% of double heterozygous embryos develop edemas along their back

pallor ( J:123073 )

• at E14.5 amd E16.5, double heterozygotes display a pale body color