The cell surface tyrosine kinase receptor PDGFRA (platelet derived growth factor receptor, alpha polypeptide) is critical in embryonic development (in particular, skeletal development and neural tube closure), and in cell proliferation, migration, and differentiation. Mutations in and fusion genes including the human PDGFRA gene are associated with cancers such as chronic myeloid leukemia, hematolymphoid neoplasm, and gastrointestinal stromal tumors.
These mice carry a point mutation in the PI3K (phosphatidylinositol 3-kinase) binding site. PI3K is the major downstream effector protein of PDGFRA.

Mice that are heterozygous for the knock-in targeted mutation are viable and fertile. Homozygotes exhibit a neonatal lethal phenotype: most homozygotes die just after birth, any surviving homozygotes die by postnatal day 16.
Expression of PDGFRA receptor protein in homozygotes is similar to wildtype control levels as detected by Western blots of knock-in mutant embryo and primary mesenchymal cell lysates.
Homozygotes that survive past the neonatal stage are 40% smaller in size than wildtype controls and exhibit cleft palate with incomplete penetrance (71%). Newborn homozygotes have an emphysema-like lung phenotype with failed alveolar septation, and abnormal skeletal development (abnormal cervical vertebrae, abnormal shoulder girdle, spina bifida, failed sternum closure). Hypomyelination is observed in the cerebellum, corpus callosum and spinal cord, but not in all regions of the CNS.
Homozygous E18.5 embryos display defective somite-derived cell migration and impaired lumbar vertebral arch formation.
Akt (protein kinase B)is not phosphorylated in homozygous animals. Heterozygous embryos have fewer oligodendrocyte progenitor cells compared with wildtype controls and exhibit impaired oligodendrocyte progenitor cell migration. These mice still carry the neo selection cassette.