Mouse Genome Informatics
hm1
    Npr2cn/Npr2cn
AKR/J
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
mortality/aging
• many die before weaning from malocclusion
• some die between weaning and 3 months of age from cyanosis

cardiovascular system

craniofacial
• bull dog-like appearance due to the domed head and shortened upper jaw
• skull width is reduced to 95% of normal
• skull length and width is reduced to 77% and 95%, respectively, of normal
• short nose with a broad transverse depression across the base

growth/size
• organ weights at 17-34 days of age are about 37-60% of normal
• organ weights at 60 days of age are about 56-98% of normal
• at birth, weigh slighly less than controls and adults never attain normal weight
• during the first few weeks, growth is greatly retarded

limbs/digits/tail
• short thick toes
• tail is reduced to 51% of normal

skeleton
• proliferating cartilage cell columns are shorter
• thinner epiphyseal plate
• lengths of limb bones are 60 to 72% of normal
• reduced width of scapula
• axial skeleton is reduced to 68% of normal
• skull width is reduced to 95% of normal
• skull length and width is reduced to 77% and 95%, respectively, of normal
• primary trabeculae are shorter, less numerous, and not aligned as well as in controls

respiratory system
• short nose with a broad transverse depression across the base

homeostasis/metabolism
• some die from cyanosis

reproductive system
• neither sex breeds well

hematopoietic system
• spleen size is 37% of normal

immune system
• spleen size is 37% of normal

Mouse Models of Human Disease
OMIM IDRef(s)
Achondroplasia; ACH 100800 J:26341


Mouse Genome Informatics
hm2
    Npr2cn/Npr2cn
involves: AKR/J
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
nervous system
• a small percentage of sensory axons extend directly towards the central canal unlike in wild-type mice
• the dorsal funiculus is reduced in size compared to in wild-type mice

skeleton
• growth of femora and tibiae is sub-normal in pre-wean homozygotes and growth is severely interupted at weaning, between 21 and 28 days of age, before resuming slow growth


Mouse Genome Informatics
hm3
    Npr2cn/Npr2cn
Not Specified
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
skeleton
• endochondral bones are markedly reduced in length but not in width
• disruption of the proximal tibial plate
• Background Sensitivity: modifiers may be responsible for 2 non-overlapping groups of 22 day old mice homozygous mice in a segregating stock; one group with marginal, one with serious disruption of the proximal tibial growth plate
• a larger than normal accumulation of glycogen is seen
• many hypertrophic chondrocytes fail to degenerate

craniofacial
• endochondral bones are markedly reduced in length but not in width


Mouse Genome Informatics
ht4
    Npr2cn/Npr2slw
involves: AKR/J * C57BL/6 * DDY
Key:
phenotype observed in females WTSI Wellcome Trust Sanger Institute
phenotype observed in males EuPh Europhenome
N normal phenotype
growth/size
• abnormal endochondral ossification leads to a short-limbed dwarfism in mice confirming the "slw" mutation is an allele of the Npr2 gene locus