Phenotypes associated with this allele

• Allele Symbol: Tbc1d20^bs
• Allele Name: blind-sterile
• Allele ID: MGI:1856684
• Summary: 2 genotypes

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Tbc1d20^bs/Tbc1d20^bs	129S;AKR-Tbc1d20^bs/J	MGI:4430075
hm2	Tbc1d20^bs/Tbc1d20^bs	involves: AKR/J	MGI:2658839

Genotype
MGI:4430075

hm1

• Allelic Composition: Tbc1d20^bs/Tbc1d20^bs
• Genetic Background: 129S;AKR-Tbc1d20^bs/J

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

reproductive system

absent acrosome ( J:206668 )

♂ • failure of acrosome formation in spermatids

decreased male germ cell number ( J:206668 )

♂ • depletion of germ cells in the testes

♂ • however, the numbers of spermatogonia or Sertoli cells are normal

abnormal seminiferous tubule epithelium morphology ( J:206668 )

♂ • increase in the number of TUNEL+ cells in the seminiferous epithelia

small testis ( J:206668 )

♂ • in adults

arrest of spermatogenesis ( J:88151 )

♂ • the most advanced spermatogenic cells found are round spermatids, and no elongated spermatids or spermatozoa are found, but these round spermatids can be used successfully in the generation of offspring via the round spermatid injection (ROSI) technique

cellular

abnormal cell morphology ( J:206668 )

• mouse embryonic fibroblasts exhibit aberrant lipid droplet formation, showing a greater number of lipid droplets after oleic acid treatment

absent acrosome ( J:206668 )

♂ • failure of acrosome formation in spermatids

decreased male germ cell number ( J:206668 )

♂ • depletion of germ cells in the testes

♂ • however, the numbers of spermatogonia or Sertoli cells are normal

abnormal Golgi apparatus morphology ( J:206668 )

• mouse embryonic fibroblasts exhibit enlarged Golgi

endocrine/exocrine glands

abnormal seminiferous tubule epithelium morphology ( J:206668 )

♂ • increase in the number of TUNEL+ cells in the seminiferous epithelia

small testis ( J:206668 )

♂ • in adults

vision/eye

abnormal lens morphology ( J:206668 )

• by P28, severe lens degeneration with large vacuoles in the lens body

ruptured lens capsule ( J:206668 )

• rupture of the lens capsule and lentricular material in the vitreous cavity is seen by P28

abnormal lens fiber morphology ( J:206668 )

• lenses at E17.5 exhibit degenerated nuclear fibers with small vacuoles between cortical fibers

• by P10, lenses exhibit severely degenerated TUNEL+ nuclear fiber cells

cataract ( J:206668 )

• nuclear opacities are seen in the eyes at P14 that progress to total opacities with irregularly patterned vacuoles by P28

small lens ( J:206668 )

• lenses at E15.5 appear normal, however at E17.5, they are smaller in size

nervous system

nervous system phenotype ( J:206668 )

♂N • no obvious brain abnormalities are seen

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
Warburg micro syndrome 4		DOID:0110719	OMIM:615663	J:206668

Genotype
MGI:2658839

hm2

• Allelic Composition: Tbc1d20^bs/Tbc1d20^bs
• Genetic Background: involves: AKR/J

cellular

abnormal male germ cell morphology ( J:8222 )

♂ • large numbers of degenerating immature germ cells are seen in the epididymides

oligozoospermia ( J:7104 , J:8222 )

♂ • vas deferens rarely contains sperm (J:7104)

♂ • 61% of males have no sperm in the epididymis or the vas deferens while the rest have reduced sperm numbers (J:8222)

teratozoospermia ( J:8222 )

♂ • 38% of males have sperm that contain mitochondrial clusters but no apparent nuclei

♂ • 7% of males have sperm in which highly looped tails wrap around abnormally shaped nuclei

abnormal sperm head morphology ( J:8222 )

♂ • all sperm exhibit an aberrant head shape, with 55% showing a sperm head that is folded back on the middle piece and contains an abnormally shaped nucleus

absent acrosome ( J:8222 )

♂ • EM analysis shows only a thickening of the nuclear envelope in the region where the acrosome should be

immotile sperm ( J:8222 )

♂ • sperm that are present are non-motile

vision/eye

cataract ( J:8222 )

developmental cataract ( J:7104 )

• bilateral lenticular cataracts in both sexes

• present at E16 in the center of lens

• easily seen through eyelids of albino mice at birth and easily recognizeable in adults

microphthalmia ( J:7104 )

• slightly smaller eyes than wild-type

reproductive system

abnormal male germ cell morphology ( J:8222 )

♂ • large numbers of degenerating immature germ cells are seen in the epididymides

oligozoospermia ( J:7104 , J:8222 )

♂ • vas deferens rarely contains sperm (J:7104)

♂ • 61% of males have no sperm in the epididymis or the vas deferens while the rest have reduced sperm numbers (J:8222)

teratozoospermia ( J:8222 )

♂ • 38% of males have sperm that contain mitochondrial clusters but no apparent nuclei

♂ • 7% of males have sperm in which highly looped tails wrap around abnormally shaped nuclei

abnormal sperm head morphology ( J:8222 )

♂ • all sperm exhibit an aberrant head shape, with 55% showing a sperm head that is folded back on the middle piece and contains an abnormally shaped nucleus

absent acrosome ( J:8222 )

♂ • EM analysis shows only a thickening of the nuclear envelope in the region where the acrosome should be

immotile sperm ( J:8222 )

♂ • sperm that are present are non-motile

small testis ( J:8222 )

♂

decreased testis weight ( J:8222 )

♂ • testis weights average about 1/3 to 1/2 that of controls

abnormal spermiogenesis ( J:8222 )

♂ • complete failure of acrosome assembly in spermatids

arrest of spermatogenesis ( J:7104 )

♂ • spermatogenesis appears to arrest after the formation of the spermatid

male infertility ( J:7104 , J:8222 )

♂ (J:7104)

♂ (J:8222)

endocrine/exocrine glands

small testis ( J:8222 )

♂

decreased testis weight ( J:8222 )

♂ • testis weights average about 1/3 to 1/2 that of controls

integument

shiny fur ( J:7104 )

• glossy coat