Somatic KRAS mutations are often detected in patients with solid and non-solid tumors, whereas germline KRAS mutations are implicated in patients with the Noonan syndrome, cardio-facio-cutaneous (CFC) syndrome and Costello syndrome.
Germline changes in the genes encoding members of the RAS subfamily of GTPases are rare and associated with variable phenotypes of the RASopathy spectrum, ranging from Costello syndrome (HRAS variants) to Noonan and Cardiofaciocutaneous syndromes (KRAS variants).
PTPN11 (39.0%), SOS1 (20.3%), RAF1 (6.8%), KRAS (5.1%), and BRAF (1.7%) mutations were identified in NS; BRAF (41.2%), SHOC2 (23.5%), and MEK1 (5.9%) mutations in cardiofaciocutaneous syndrome; and HRAS and PTPN11 mutations in Costello syndrome and LEOPARD syndrome, respectively.
Germline KRAS mutations were shown recently to be associated with developmental disorders, including Noonan syndrome (NS), cardio-facio-cutaneous syndrome (CFCS), and Costello syndrome (CS).
We identified four different missense mutations of HRAS in twenty-eight cases with CS (90.3%), while KRAS mutations were detected in two infants with a phenotype meeting criteria for CS (6.5%).
We report on a novel KRAS gene mutation in a patient presenting the clinical features typical of Costello syndrome and the additional findings seen in Noonan syndrome.
Remarkably, our cohort of individuals with KRAS mutations showed a high clinical variability, ranging from Noonan syndrome to CFC, and also included two patients who met the clinical criteria of Costello syndrome.
Germ line missense mutations in HRAS and KRAS and in genes encoding molecules that function up- or downstream of Ras in cellular signaling networks cause a group of related developmental disorders that includes Costello syndrome, Noonan syndrome, and cardiofaciocutaneous syndrome.
We report on a novel KRAS gene mutation in a patient presenting the clinical features typical of Costello syndrome and the additional findings seen in Noonan syndrome.
Remarkably, our cohort of individuals with KRAS mutations showed a high clinical variability, ranging from Noonan syndrome to CFC, and also included two patients who met the clinical criteria of Costello syndrome.
We have observed unusual transverse distal phalangeal creases in two patients, one with Costello syndrome (G12S mutation in the HRAS gene) and one with cardio-facio-cutaneous (CFC) syndrome or possibly Noonan syndrome (Q22E mutation in the KRAS gene).
We report on a novel KRAS gene mutation in a patient presenting the clinical features typical of Costello syndrome and the additional findings seen in Noonan syndrome.