Since investigations began in 1999, multiple illnesses, ailments, and deformation processes have been suggested to explain the appearance and composition of the Starchild Skull.
Each of these suggestions has been taken seriously, and conscientious research has been undertaken to try and find a simple medical reason for the anomalous skull. At this time, no known medical condition or cultural practice has been identified that can explain the Starchild Skull.
Conditions Commonly Suggested To Explain The Starchild Skull:
Cradleboarding (and other artificial cranial deformations)- Processes where pressure is applied either intentionally or accidentally to the soft skull of an infant to give it an abnormal shape. This condition was ruled out in a 2004 Study led by Dr. T.J. Robinson.
Hydrocephaly- A condition where an abnormal accumulation of cerebrospinal fluid in the cranium causes an increase in internal pressure that pushes outward against the skull, giving it an unusual "inflated" shape. This condition was specifically rued out by Dr. Bachynsky and Dr. Robinson.
Morgellons Disease- A currently unclassified medical condition which, among other things, often manifests as skin lesions with clusters of fibers embedded in the skin. These fibers are present in the soft tissue such as skin, and visible to the naked eye, unlike the microscopic fibers inside the Starchild Skull's bone.
Progeria (Hutchinson-Gilford Syndrome)- A rare fatal genetic disorder characterized by the dramatic, rapid appearance of aging beginning in childhood. While some of the features of this condition resemble those of the Starchild, key elements are missing. In cases of Progeria the bone only becomes thinner due to osteoporosis, which clearly is not present in the Starchild, and while the skulls of progeria victims look more promienent, they remain human-shaped with normal sized brains, compared to the unusual shape and 30% larger brain of the Starchild Skull. Progeria can also cause premature fusion of the cranial sutures, which has been ruled out in the Starchild.
Apert Syndrome- A genetic disorder primarily characterized by prematurely fused sutures in the skull, and a retruded/ sunken midfacial area. A CAT scan has ruled out this condition, and shows no premature fusion of any sutures.
Brachycephaly- A broad term used to describe skulls which are disproportionately wide, a condition that can be caused by artificial cranial deformation, or premature fusion of the sutures as in Apert Syndrome. A CAT scan has ruled out this condition, and shows no premature fusion of any sutures.
Cruzon Syndrome- A hereditary condition that causes premature fusion of the cranial sutures, and can cause exopthalmos (shallow eye sockets), and incomplete development of the midface. A CAT scan has ruled out this condition, and shows no premature fusion of any sutures.
The conditions listed above are among many many possibilities that have been examined as the cause of the unusual characteristics of the Starchild Skull, but so far no condition or combination of conditions has been found that explains the skull. It is not a known deformity. It is completely unique, and only finishing the DNA testing will be able to truly answer the question of what it is.