Phenotypes Associated with This Genotype

Genotype
MGI:2175217

• Allelic Composition: Irs4^tm1Lhd/Irs4^tm1Lhd
• Genetic Background: involves: 129S4/SvJae * C57BL/6

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

reproductive system

abnormal fertility/fecundity ( J:59964 )

♀ • female homozygotes exhibit reduced ability to produce live offspring when mated with hemizygous mutant males

decreased litter size ( J:59964 )

♀ • pairs of mutant mice produce an average of 1.8 0.4 litters per pair (range 0-3 litters) over a 3-month period, whereas wild-type mice produce an average of 2.9 0.1 litters per pair (range 2-3 litters)

♀ • 36% of mutant litters die within a few days of birth relative to only 5% of wild-type litters

♀ • the average size of surviving litters from mutant mice is slightly reduced relative to wild-type litters

behavior/neurological

abnormal maternal nurturing ( J:59964 )

♀ • female homozygotes may be less nurturing of their pups than wild-type females, as suggested by an observed decrease in the number of surviving litters

homeostasis/metabolism

homeostasis/metabolism phenotype ( J:59964 )

♀N • female homozygotes show slightly reduced blood glucose levels in both the fasted and fed states at 6-10 weeks, and in the fed state at 6 months; however, none of these differences reach statistical significance

♀N • in addition, plasma insulin levels remain unaffected in the fed and fasted state at both ages

abnormal glucose tolerance ( J:59964 )

♀ • at 6 months, older female homozygotes exhibit only a very slightly impaired glucose tolerance, which is statistically significant at 10 min but not at other time points

growth/size/body

growth/size/body region phenotype ( J:59964 )

♀N • female homozygotes exhibit a very slight reduction in body size relative to wild-type mice; however, this difference does not reach statistical significance