Lissencephaly is a brain malformation, in which the brain does not fully develop the gyri or ridges that cover the surface of the brain. Lissencephaly can be caused by a genetic mutation of at least two different genes on chromosome seventeen and X-chromosome called doublecortin. It could also be caused by a viral infection. It is also most common in Miller-Dieker syndrome and Norman-Roberts syndrome (“Lissencephaly”,2012). Miller-Dieker is a condition where an individua has facial abnormalities that include a prominent forehead, sunken appearance of face, small, upturned nose, abnormally shaped ears, small jaw, and a thick upper lip. People with Miller-Dieker also grow more slowly than others, and very rarely some have heart/kidney malformations or missing a wall of their abdomen where you can see their organs protruding through the …show more content…
The symptoms tend to worsen the more underdeveloped the gyri and ridges are. In addition to Lissencephaly, there is an underdevelopment of the nerve fibers that carry messages between the two hemispheres of the brain. A way to know if an individual has Lissencephaly is if they have slight indentions in their temples or an unusually small jaw. This disease also happens to stunt growth or stop it altogether, and hypertonia—increased muscle tone, during infancy—and hypotonia early in infancy. In males are more affected by this disease than females that result in more severe symptoms. Males receive the full spectrum of abnormalities, which include a complete absence of the nerve fibers that connect the brain hemispheres, intractable seizures, profound intellectual impairment, growth failure. In females have abnormal bands of brain tissue on the cerebral cortex—subcortical heterotopia or double cortex—and they have less severe seizures than those of males. (Nall,