Neural crest
The syndrome is caused by mutations in any of several genes that affect the division and migration of neural crest cells during embryonic development (though some of the genes involved also affect the neural tube). Neural crest cells are stem cells left over after the closing of the neural tube that go on to form diverse non-central nervous system cells in different parts of the body, including melanocytes, various bones and cartilage of the face and inner ear and the peripheral nerves of the intestines. Type 1 is caused by a mutation in the "PAX3" gene, while the gene that most often causes type 2 when mutated is "MITF". Type 3 is a more severe presentation of type 1 and is caused by a mutation in the same gene, while type 4 is most often caused by a mutation in "SOX10". Mutations in other genes can also cause the different types, and some of these have been given their own lettered subtypes. Most types are autosomal dominant.