Phenotypes Associated with This Genotype

Genotype
MGI:3763181

• Allelic Composition: Gja1^tm7(Gja2)Kwi/Gja1^tm7(Gja2)Kwi
• Genetic Background: involves: 129P2/OlaHsd * C57BL/6 * SJL

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

Tubuli seminiferi and ductuli epididymidis of wild type and Gja1^tm7(Gja2)Kwi/Gja1^tm7(Gja2)Kwi mice

cellular

azoospermia ( J:126511 )

♂ • no sperm are detected in the epididymis

♂ • however, intratesticular testosterone levels are normal

abnormal spermatocyte morphology ( J:126511 )

♂ • only sporadic primary spermatocytes are observed

mortality/aging

postnatal lethality, incomplete penetrance ( J:126511 )

• fewer than expected mice survive to weaning and beyond (6% compared to the expected 25%)

• increased mortality is associated with having a heterozygous mother

• however, survival can be improved by fostering mice to wild-type mothers

prenatal lethality, incomplete penetrance ( J:126511 )

• fewer than expected mice are born (17% compared to the expected 25%)

reproductive system

absent corpus luteum ( J:126511 )

♀

abnormal ovarian follicle number ( J:126511 )

♀ • ovaries contain only a few follicles

impaired ovarian folliculogenesis ( J:126511 )

♀ • the full range of follicle stages is missing

♀ • the maturation of follicles is arrested at the early secondary stage with most follicles missing oocytes

small ovary ( J:126511 )

♀

ovary cyst ( J:126511 )

♀ • in extreme cases the ovary is displaced by one big cyst

decreased testis weight ( J:126511 )

♂ • testis weight is reduced to one forth of wild-type in all males

abnormal spermatogenesis ( J:126511 )

♂ • differentiated stages of spermatogenesis are absent

♂ • with the exception of sporadic spermatocytes, no spermatozoa or other stages of spermatogenesis are found

azoospermia ( J:126511 )

♂ • no sperm are detected in the epididymis

♂ • however, intratesticular testosterone levels are normal

abnormal spermatocyte morphology ( J:126511 )

♂ • only sporadic primary spermatocytes are observed

female infertility ( J:126511 )

♀

male infertility ( J:126511 )

♂

cardiovascular system

small heart ( J:126511 )

• unlike other Gja1 deficient mice, only the size of the heart is smaller in neonates

• 95+/-24 mg compared to 121+/-26 mg for wild-type mice

• however, left-ventricular mass and ejection fraction are normal in neonates while heart rate and ejection volume are normal in adults

abnormal cardiovascular system physiology ( J:126511 )

decreased heart rate ( J:126511 )

• 300+/-70 beats per minute compared to 346+/-80 beats per minute in wild-type neonates

• however, there is no difference in electrocardiogram readings for neonates

abnormal atrioventricular bundle conduction ( J:126511 )

• infra-Hisian conduction is impaired (9.5+/-0.7 ms compared to 12.4+/-2.4 ms in wild-type mice)

prolonged QRS complex duration ( J:126511 )

• hearts exhibit prolonged QRS (10.9+/-0.6 ms compared to 9.1+/-0.7 ms in wild-type hearts)

shortened QT interval ( J:126511 )

• hearts exhibit shorter rate-corrected QTc-intervals (12.2+/-1.1 ms compared to 16.0+/-2.6 ms for wild-type hearts) in surface electrocardiogram

growth/size/body

ovary cyst ( J:126511 )

♀ • in extreme cases the ovary is displaced by one big cyst

decreased body weight ( J:126511 )

• mice weigh is reduced by 30% (20+/-2 g compared to 31+/-3 g for wild-type mice)

postnatal growth retardation ( J:126511 )

endocrine/exocrine glands

absent corpus luteum ( J:126511 )

♀

abnormal ovarian follicle number ( J:126511 )

♀ • ovaries contain only a few follicles

impaired ovarian folliculogenesis ( J:126511 )

♀ • the full range of follicle stages is missing

♀ • the maturation of follicles is arrested at the early secondary stage with most follicles missing oocytes

small ovary ( J:126511 )

♀

ovary cyst ( J:126511 )

♀ • in extreme cases the ovary is displaced by one big cyst

decreased testis weight ( J:126511 )

♂ • testis weight is reduced to one forth of wild-type in all males