Phenotypes associated with this allele

• Allele Symbol: Btbd18^tm1Dean
• Allele Name: targeted mutation 1, Jurrien Dean
• Allele ID: MGI:5888779
• Summary: 1 genotype

Jump to	Allelic Composition	Genetic Background	Genotype ID
hm1	Btbd18^tm1Dean/Btbd18^tm1Dean	involves: 129S4/SvJae * C57BL/6	MGI:7560663

Genotype
MGI:7560663

hm1

• Allelic Composition: Btbd18^tm1Dean/Btbd18^tm1Dean
• Genetic Background: involves: 129S4/SvJae * C57BL/6

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

reproductive system

increased male germ cell apoptosis ( J:240025 )

♂ • male germ cells become apoptotic from the late spermatocyte stage

increased testis apoptosis ( J:240025 )

♂ • TUNEL analysis indicates a significant increase in apoptosis within seminiferous tubules

♂ • elevated testis apoptosis is noted from P18 and increases significantly at P28

small testis ( J:240025 )

♂ • at 8 weeks of age, testes are significantly smaller than wild-type testes

decreased testis weight ( J:240025 )

♂ • significantly decreased testes to body weight ratio at 8 weeks of age

abnormal gametogenesis ( J:240025 )

♂ • expression of a subset of pachytene piRNA precursors is significantly reduced and pachytene piRNA production is severely impaired in adult testes

abnormal spermatid morphology ( J:240025 )

♂ • males show significantly reduced formation of round spermatids

♂ • development of round spermatids is arrested at step 3-5

decreased male germ cell number ( J:240025 )

♂ • males show significantly reduced formation of round spermatids

azoospermia ( J:240025 )

♂ • no spermatozoa are present in testes at 4 months of age

arrest of spermatogenesis ( J:240025 )

♂ • males show a post-meiotic blockage at the round spermatid stage

♂ • however, meiotic synapsis and recombination are normal

arrest of spermiogenesis ( J:240025 )

♂ • development of round spermatids is arrested at step 3-5, in the absence of retrotransposon derepression

male infertility ( J:240025 )

♂ • male homozygotes are sterile; no pups are produced when homozygous null males are co-caged with heterozygous or homozygous null females

endocrine/exocrine glands

increased testis apoptosis ( J:240025 )

♂ • TUNEL analysis indicates a significant increase in apoptosis within seminiferous tubules

♂ • elevated testis apoptosis is noted from P18 and increases significantly at P28

small testis ( J:240025 )

♂ • at 8 weeks of age, testes are significantly smaller than wild-type testes

decreased testis weight ( J:240025 )

♂ • significantly decreased testes to body weight ratio at 8 weeks of age

embryo

embryo phenotype ( J:240025 )

• normal-appearing pups are produced by mating females homozygotes with heterozygous null males, indicating normal embryogenesis

cellular

abnormal spermatid morphology ( J:240025 )

♂ • males show significantly reduced formation of round spermatids

♂ • development of round spermatids is arrested at step 3-5

decreased male germ cell number ( J:240025 )

♂ • males show significantly reduced formation of round spermatids

azoospermia ( J:240025 )

♂ • no spermatozoa are present in testes at 4 months of age

increased male germ cell apoptosis ( J:240025 )

♂ • male germ cells become apoptotic from the late spermatocyte stage

increased testis apoptosis ( J:240025 )

♂ • TUNEL analysis indicates a significant increase in apoptosis within seminiferous tubules

♂ • elevated testis apoptosis is noted from P18 and increases significantly at P28