XK aprosencephaly is a very rare disorder that affects the brain and other parts of the body. People with this condition have a type of cerebral malformation called aprosencephaly, which means that parts of the brain (the telencephalon and diencephalon) do not develop. In addition to these brain changes, there are also facial and limb anomalies. For example, some individuals may have differences in the eyes and face such as reduced distance between the eyes or even a single eye (cyclopia), problems with nasal structures, or a cleft lip. Other features of the condition include abnormalities in the limbs, such as small or missing parts of the hands or feet. There may also be issues affecting other parts of the body like ambiguous genitalia, an imperforate anus (where the anus does not develop properly), and problems with the spine.

The symptoms of XK aprosencephaly include major brain malformations (specifically, the absence of the telencephalon and diencephalon), unusual facial features including ocular hypotelorism or cyclopia and nasal malformations, cleft lip, and limb abnormalities such as hypoplastic hands or absent great toes. Other symptoms can include ambiguous genitalia, imperforate anus, and vertebral anomalies.

The condition is thought to be inherited in an autosomal recessive manner, meaning that two copies of the gene may be required for a person to develop XK aprosencephaly. Further details about the genetic causes or specific risk factors are not provided in the current sources.