All Phenotypes Hmx3/Hmx2<tm3Tlu> MGI Mouse

mortality/aging

postnatal lethality, complete penetrance ( J:92940 )

• about 90% of homozygotes die by P5 with none surviving beyond P9

behavior/neurological

impaired balance ( J:92940 )

• homozygotes show a total loss of balance and inability to right themselves

endocrine/exocrine glands

small adenohypophysis ( J:92940 )

• the anterior lobe of the pituitary gland is severely reduced in size out of proportion to the reduction in body size

small pituitary gland ( J:92940 )

• most of the pituitary gland is reduced in size in proportion to the reduction in body size

growth/size/body

postnatal growth retardation ( J:92940 )

• homozygotes display a severe developmental delay from P3 onward and by the time of death are less than 1/3 the weight and the length of their wild-type littermates

hearing/vestibular/ear

decreased vestibular hair cell number ( J:92940 )

• sensory hair cell numbers are decreased around 100-fold with a 2-fold increase in the density of apoptotic bodies at E15.5 and E16.5

absent semicircular canals ( J:92940 )

• loss of the semicircular canals is seen by E14.5

abnormal membranous labyrinth morphology ( J:92940 )

• the overall structure of the membranous labyrinth is barely recognizable at E16.5

utricular degeneration ( J:92940 )

• the utricle measures less than 1% of the expected volume at E15.5 and is lost by E18.5

vestibular saccular degeneration ( J:92940 )

• the saccule measures less than 5% of the expected volume at E14.5 and is lost by E18.5

abnormal endolymphatic duct morphology ( J:92940 )

• the endolymphatic duct and sac appear normal at E12.5 but fail to proliferate by E14.5

homeostasis/metabolism

decreased circulating growth hormone level ( J:92940 )

• growth hormone levels are decreased more than 40%

muscle

muscle spasm ( J:92940 )

• frequent muscle spasms are seen

nervous system