Cardiofaciocutaneous syndrome (CFCS) is a rare developmental disorder that is phenotypically similar to Noonan syndrome and is associated with mutations in BRAF, MEK1, MEK2, and KRAS.
Cardiofaciocutaneous syndrome (CFCS) is a rare developmental disorder that is phenotypically similar to Noonan syndrome and is associated with mutations in BRAF, MEK1, MEK2, and KRAS.
A 7-year-8-month-old boy with cardiofaciocutaneous syndrome caused by the D638E mutation of the B-Raf proto-oncogene (BRAF) presented with new-onset seizures.
Although this mutation is one of the most common mutations in CFC, to our knowledge, this is the first molecularly confirmed BRAF mutation causing CFC in siblings.
However, despite reduced levels of MEK1 protein and the lower abundance of MEK1Y130C protein than wild type, <i>Mek1</i><sup>Y130C</sup> mutants showed increased ERK (MAPK) protein activation in response to growth factors, supporting a role for MEK1Y130C in hyperactivation of the RAS/MAPK pathway, leading to CFC.
Here, we describe patients with craniosynostosis and Noonan syndrome due to de novo mutations in PTPN11 and patients with craniosynostosis and CFC syndrome due to de novo mutations in BRAF or KRAS.
Here, we describe patients with craniosynostosis and Noonan syndrome due to de novo mutations in PTPN11 and patients with craniosynostosis and CFC syndrome due to de novo mutations in BRAF or KRAS.
Mutations in MAP2K1, a gene expressed within the RAS-mitogen activated protein kinase (RAS/MAPK) pathway, are generally associated with the clinical phenotype of cardiofaciocutaneous syndrome.
Germline mutations in BRAF are a major cause of cardio-facio-cutaneous (CFC) syndrome, which is characterized by heart defects, characteristic craniofacial dysmorphology and dermatologic abnormalities.
As the role of the RAS/MAPK pathway in HCM pathogenesis is unclear, we generated a human induced pluripotent stem cell (hiPSC) model for CFCS from three patients with activating BRAF mutations.
None of the patients of our series with CFC syndrome (with germline BRAF or MAP2K1/MAP2K2 mutation - n = 121) or Costello syndrome (with HRAS mutation - n = 35) had an ALL.
The hECTs were created using human cardiomyocytes obtained by directed differentiation of induced pluripotent stem cells derived from a patient with CFCS due to an activating BRAF mutation.
He was found to have a novel heterozygous missense variant (c.305A > G; p.E102G) in MAP2K1, a gene mostly causal for cardio-facio-cutaneous syndrome (CFCS).
We recently demonstrated that mice expressing a Braf Q241R mutation, which corresponds to the most frequent BRAF mutation (Q257R) in CFC syndrome, on a C57BL/6J background are embryonic/neonatal lethal, with multiple congenital defects, preventing us from analyzing the phenotypic consequences after birth.
Cardio-facio-cutaneous (CFC) syndrome is a developmental disorder caused by constitutively active ERK signaling manifesting mainly from BRAF mutations.