Characteristics and causes of Apert Syndrome

Apert Syndrome is a congenital disease with very distinct characteristics and a few possible causes. Congenital diseases are diseases that are present at birth and they do not appear over time. It is also considered a craniofacial and limb anomaly disease, meaning it affects the face and head as well as the arms and legs. 

Characteristics of Apert Syndrome

The major characteristics of Apert Syndrome are physical. They include fused cranial features that lead to hypoplasia in the mid-face region as well as fingers and toes that are fused together. There are a number of other conditions and features that are sometimes associated with Apert Syndrome, but it is unknown whether they are part of the defect or if they are caused by the defects. These additional characteristics are heart defects, hydrocephalous, increased number of ear infections, acne, increased number of eye injuries and polycystic kidneys. Some of the heart defects include pulmonary atresia in which the pulmonary valve fails to open normally and Patent Ductus Arteriosus in which the blood vessel allowing blood to go around the lungs before the baby is born fails to close after birth. Apert is also sometimes associated with a Tracheoesophageal Fistula, Pyloric stenosis and a bicornate uterus.

The mid-face is the part of the face roughly from the center of the eye sockets to the upper jaw. The malformations of this facial area are caused by the skull fusing together prematurely and the middle of the face growing slowly. This results in the mid-face often being sunken in or suffering from a condition called hypoplasia. The top of the face and bottom of the face grow at normal rates and create a concave appearance. The skull plates, when fusing normally, gradually grow together as the baby gets older. In Apert children, there is a great deal of pressure on the brain and also very restricted brain growth in addition to affecting the facial structure. 

The fusion of fingers and toes is known as syndactyly. In Apert Syndrome this always involves the connecting of the first, middle and ring fingers. The bones are often fused together and there is no mobility of the fingers beyond the first joint. The thumbs are sometimes fused to the hand, but other times they are not. This fusion comes in varying degrees depending upon the extent of the condition.  

Causes of Apert Syndrome

Apert Syndrome is a genetic defect, but it is not considered recessive nor dominant. Instead it tends to be an abnormal mutation. If one parent has Apert, then there is a fifty percent chance that they will pass it on to their child. Cases of Apert Syndrome are either the result of inheritance if one parent suffers from Apert Syndrome or it can also be caused by a new genetic mutation. When it is the latter, it most often occurs when the father of the child is older and the genetic change occurs on chromosome number ten. The gene in question is known as Fibroblast Growth Factor Receptor Two.