TCF20 and craniosynostosis: While this work was being undertaken, we coincidentally discovered a further TCF20 mutation during an unrelated project aimed at identifying novel genetic causes of craniosynostosis.36 The exome sequence from a woman with unicoronal synostosis segregating from her mother (family #6) was found to contain a heterozygous one-nucleotide deletion of TCF20 (c.3518delA encoding p.K1173Rfs*5).