Burn-Mckeown syndrome (MIM 608572) is an ultra-rare autosomal recessive disorder due to biallelic variants in the TNXL4A gene. Affected individuals have variable clinical features. Choanal atresia is a consistent feature. Many affected individuals have facial dysmorphisms including short palpebral fissures, coloboma of the lower eyelids, and sensorineural hearing loss. Some clinical overlap is noted with Treacher Collins syndrome (but this is inherited in a dominant pattern). Burn Mckeown syndrome is genetically homogeneous.
A small number of individuals have been described with isolated choanal atresia with homozygosity for variants in the TXNL4A promoter.