SOS1 and Noonan syndrome: The following whole exome sequencing ruled out any compound heterozygosity and revealed a heterozygous pathogenic variation in the SOS1 gene (NM_005633.4:c.1644T>A, p.Ser548Arg) that confirmed Noonan syndrome 4 (Phenotype MIM number: 610733, location: 2p22.1, Gene/Locus MIM number: 182530).