CFC syndrome is the largest reported to date. BRAF mutations are documented in 140 individuals ($75%), while 46 ($25%) have a mutation in MEK 1 or MEK 2. The age range is 6 months to 32 years, the oldest individual being a female from the original report [Reynolds et al.(1986); Am J Med Genet 25: 413–427]. While some clinical data on 136 are in the literature, 50 are not previously published. We provide new details of the breadth of phenotype and discuss the frequency of particular features in each genotypic group. Pulmonary stenosis is the only anomaly that demonstrates a statistically significant genotype–phenotype correlation, being more common in individuals with a BRAF mutation.© 2011 Wiley-Liss, Inc.