Phenotypes Associated with This Genotype

Genotype
MGI:5755097

cn18

• Allelic Composition: Nras^tm1Tyj/Nras^tm1Tyj; Tg(Tyr-cre)1Lru/0
• Genetic Background: involves: C57BL/6 * DBA/2

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

skeleton

abnormal cranium morphology ( J:198244 )

• most mice develop increasing cranial perimeter or cranial deformity

cellular

abnormal melanocyte proliferation ( J:198244 )

• increase in proliferation of leptomeningeal pigmented melanocytes

behavior/neurological

abnormal behavior ( J:198244 )

• symptoms progress rapidly to akathisia and general malaise

hyperresponsive to tactile stimuli ( J:198244 )

• at a median age of 4 months

tremors ( J:198244 )

• seen at a median age of 4 months

impaired coordination ( J:198244 )

• mice exhibit incoordination at a median age of 4 months

abnormal gait ( J:198244 )

• mice show impaired gait at a median age of 4 months

mortality/aging

premature death ( J:198244 )

• mice die before 12 months of age

craniofacial

abnormal cranium morphology ( J:198244 )

• most mice develop increasing cranial perimeter or cranial deformity

integument

abnormal skin morphology ( J:198244 )

• mice develop benign paucicellular dermal melanocytic lesions resembling human blue nevi

pigmentation

abnormal melanocyte proliferation ( J:198244 )

• increase in proliferation of leptomeningeal pigmented melanocytes

abnormal leptomeninges pigmentation ( J:198244 )

• brains show darkening of the leptomeninges that follows the sulci and fissures, and is more prominent in the frontoparietal region

• increase in the number of pigmented melanocytes that follow the gyri and sulci and envelop the ventricles (melanocytosis)

abnormal melanocyte morphology ( J:198244 )

• hyperpigmented dendritic melanocytes are seen in 3 week old and adult mice, particularly between the collagen bundles of the reticular dermis and along the adnexae of the deep dermal layers

hyperpigmentation ( J:198244 )

• darkening of the skin, tails, paws, and snouts that is evident from day 1 and persists throughout life

neoplasm

increased melanoma incidence ( J:198244 )

• darkly pigmented areas in the brain are composed of large melanocytic lesions comprising pleomorphic cells that invade the brain parenchyma with tumor cells rapidly dividing, indicating primary melanoma of the central nervous system

• however, mice do not develop cutaneous melanoma or tumors in the uvea, hearts, or oral and genital mucosa

• tumor cells frequently present intracytoplasmic melanin