Any Treacher-Collins syndrome in which the cause of the disease is a mutation in the TCOF1 gene. The disease is Treacher Collins syndrome 1 (Monarch Disease Ontology identifier MONDO_0007944). Also known as: TCOF1 Treacher-Collins syndrome, Treacher Collins syndrome type 1, Treacher-Collins syndrome 1, Treacher-Collins syndrome caused by mutation in TCOF1.