Exencephaly is a type of cephalic disorder wherein the brain is located outside of the skull.
It is rare to find an infant born with exencephaly, as most cases that are not early stages of anencephaly are usually stillborn.
[2] The disorder is caused by the failure of cranial neuropore to properly fuse between the 3rd and 4th week post conception.
As a result of new genetic research, some of these are, in fact, highly related in their root cause despite the widely varying set of medical symptoms that are clinically visible in the disorders.
The cilia defects adversely affect "numerous critical developmental signaling pathways" essential to cellular development and thus offer a plausible hypothesis for the often multi-symptom nature of a large set of syndromes and diseases.