The Mouse Adult Gross Anatomy Ontology and Mammalian Phenotype Ontology are downloaded weekly from the Mouse Genome Informatics databases at Jackson Laboratories (ftp://ftp.informatics.jax.org/pub/reports/index.html). For more information about these ontologies, see the MGI Publications Page at http://www.informatics.jax.org/mgihome/other/publications.shtml.
absence of the structure of the first arch which contributes to development of mastication muscles, maxilla, mandible, incus, malleus, Meckel's cartilage, trigeminal nerve, and maxillary artery