The patterning of embryonic ectoderm also depends on transcription factors such as Distal-less 3 (DLX3), which have different responses to BMP signaling in the ectoderm.105 DLX3 is essential for skeletal morphogenesis and acts as a scaffold for nucleic acids and regulatory factors involved in skeletal gene expression.106 In humans, mutations in DLX3 cause TDO. This evidence concerns the gene DLX3 and tricho-dento-osseous syndrome.