behavior/neurological
• noticeable by 4 weeks of age
(J:66428)
|
• exhibit repetitive wobbling behavior that is noticeable by 4 weeks of age
|
• nodding is noticeable by 4 weeks of age
(J:66428)
|
hearing/vestibular/ear
• Reissner membrane is collapsed onto the tectorial membrane
(J:66428)
|
• a denuded basilar membrane forms fibrous adhesions with the tectorial membrane and collapsed Reissner membrane
|
• hair cells of the organ of Corti are absent and are replaced by fibrous adhesions between the tectorial membrane and the basilar membrane
(J:66428)
|
• supporting cells of the organ of Corti are absent and are replaced by fibrous adhesions between the tectorial membrane and the basilar membrane
(J:66428)
|
• degeneration is more severe at the basal end
(J:66428)
|
• severe atrophy of the stria vascularis, esp. in the basal turn
• dense deposits of a hyaline material in apical turns, appearing to be an extension of the stria vascularis remnant
|
• 42 to 45% reduction in the total volume of mutant stria vascularis relative to wild-type mice
|
• the tectorial membrane shows increased density and thickness, esp. in the apical and middle turns, and is absent in the basal turn
|
• severe contraction of the scala media, particularly in the basal end
(J:66428)
• collapse of Reissner's membrane leads to a 64% and 73% reduction in the volume of scala media relative to wild-type and heterozygous mice, respectively
(J:110797)
|
• reduction in the volume of the endolymphatic compartment of the semicircular canal, associated with contraction and fibrosis of the membranous lining
|
• cystic collection of granular debris between adhesions of the outer membrane and the neuroepitheliun of the crista ampullaris
|
• reduction in the volume of the endolymphatic compartment of the vestibule, associated with contraction and fibrosis of the membranous lining
|
• the saccular macula lacks hair cells
|
• complete loss of sterocilia in the saccular maculae
• instead, a flat epithelium is found on the surface of the neuroepithelium
|
• the vestibular end organs show collapse of the membranous labyrinth
• the membranous walls of the saccule and utricle are collapsed onto the otolithic membrane
|
• utricular maculae are only modestly degenerated
|
• otoliths lack a homogeneous appearance and resemble stellate-shaped aggregates or a continuous solid mass
|
• the otolithic membrane is separated from the neuroepithelium
(J:66428)
• the otolithic membrane is separated from the neuroepithelium of the macula in both the utricle and the saccule
(J:110797)
|
• homozygotes exhibit no detectable auditory brainstem responses (ABRs) to clicks presented at 90 db or higher
• in contrast, wild-type mice display ABR thresholds ranging from 41 to 65 dB SPL (J:66428)
|
digestive/alimentary system
• intrinsic factor-expressing chief cells appear smaller and are decreased in number
|
• parietal cells are decreased in number
|
• expansion of mucous neck cells
|
• isthmic regions of the gastric glands are dilated and appear populated by mucin-secreting cells and vacuolated parietal cells
|
• antral and fundic mucosa show hyperplasia, with changes more striking in the fundus
• majority of fundic hyperplasia occurs in the middle (isthmic) portion of the mucosa and in the gastric neck (proliferative compartment)
• the proliferative compartment of the mucosa is expanded in both the antrum and fundus and is disorganized
• mucosal hyperplasia accounts for the increase in gastric wall thickness
|
• mucosal hyperplasia accounts for the increase in gastric wall thickness
|
• 3-fold enlargement of the stomach
|
• gastric lumen pH 6-7 vs. pH 1-2 in wild-type
|
cardiovascular system
N |
• normal cardiac electrophysiology
|
nervous system
• hair cells of the organ of Corti are absent and are replaced by fibrous adhesions between the tectorial membrane and the basilar membrane
(J:66428)
|
• the saccular macula lacks hair cells
|
• complete loss of sterocilia in the saccular maculae
• instead, a flat epithelium is found on the surface of the neuroepithelium
|
• homozygotes exhibit 45% and 48% fewer spinal ganglion cells relative to wild-type and heterozygous mice, respectively
• SGN degeneration occurs in all turns but is most severe in the middle and apical regions
|
homeostasis/metabolism
• elevation in serum gastrin levels
|
endocrine/exocrine glands
• intrinsic factor-expressing chief cells appear smaller and are decreased in number
|
• parietal cells are decreased in number
|
• expansion of mucous neck cells
|
• isthmic regions of the gastric glands are dilated and appear populated by mucin-secreting cells and vacuolated parietal cells
|
Mouse Models of Human Disease |
DO ID | OMIM ID(s) | Ref(s) | |
NOT | Beckwith-Wiedemann syndrome | DOID:5572 |
OMIM:130650 |
J:66428 |
Jervell-Lange Nielsen syndrome | DOID:2842 |
OMIM:220400 OMIM:612347 |
J:110797 |