Phenotypes Associated with This Genotype

Genotype
MGI:3574052

• Allelic Composition: Rb1^tm2Mlh/Rb1⁺
• Genetic Background: either: 129P2/OlaHsd-Rb1^tm2Mlh or (involves: 129P2/OlaHsd * BALB/c) or (involves: 129P2/OlaHsd * FVB/N)

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

neoplasm

neoplasm ( J:2498 , J:20542 )

N • up to 7 months of age, young heterozygotes exhibit no sign of retinoblastoma or any other abnormality relative to wild-type mice (J:2498)

N • no retinoblastomas are macroscopically detected in chimeras ranging in age up to 11 months (J:2498)

N • no pre-neoplastic lesions are detected in the medulla of the adrenal gland of heterozygous mutant mice (J:20542)

increased pituitary melanotroph tumor incidence ( J:20542 )

• after 3-5 months, heterozygotes develop large (4-5 mm) tumors in the intermediate lobe of the pituitary gland

• such tumors are relatively benign and do not infiltrate into brain tissue; the wild-type allele of Rb1 is lost in the vast majority of cases

nervous system

increased pituitary melanotroph tumor incidence ( J:20542 )

• after 3-5 months, heterozygotes develop large (4-5 mm) tumors in the intermediate lobe of the pituitary gland

• such tumors are relatively benign and do not infiltrate into brain tissue; the wild-type allele of Rb1 is lost in the vast majority of cases

abnormal dorsal root ganglion morphology ( J:2498 )

• at E11.5, heterozygotes exhibit only occasional apoptotic cells in the spinal ganglia, identified by their pyknotic and fragmented nuclei and dense eosinophilic cytoplasm

endocrine/exocrine glands

increased pituitary melanotroph tumor incidence ( J:20542 )

• after 3-5 months, heterozygotes develop large (4-5 mm) tumors in the intermediate lobe of the pituitary gland

• such tumors are relatively benign and do not infiltrate into brain tissue; the wild-type allele of Rb1 is lost in the vast majority of cases