Proteus syndrome is a very rare genetic disorder that is characterized by the over abundance of growth in tissues and bones. There is an estimated 100 individuals with Proteus syndrome out of the entire population of the world and it occurs in less than one per 1,000,000 live births. The name of this syndrome is named for the ancient Greek god Proteus who was able to take on different forms. For individuals diagnosed with Proteus syndrome, their appearance also takes on different forms as their bodies may be exhibiting the signs of usually fast growth in certain tissues, bones, and organs. Specific locations of the body that may have these usual growths cause asymmetrical shapes and give the appearance of severe lopsidedness of the effected individual.
Characteristics of Proteus syndrome include an over growth of the limbs, face, or body typically on one side (Hemihypertrophy), partially enlarged hands or feet, skin with darkened patches or a raised and rough surface, tumors on the surface or under the surface of the skin, and an overgrowth of the soft tissues on the bottom of the feet (Plantar hyperplasia). No two individuals with Proteus syndrome will have the same overgrowths. Some will exhibit very mild symptoms while others will be much more severe.
Proteus syndrome is caused by a mutation in a gene known as AKT1. In normal cases, this gene is responsible for mediating and regulating numerous cellular processes including protein synthesis, glucose transport, and neuron integration and positioning. In the case of Proteus syndrome, the mutated AKT1 gene is no longer capable of regulation and allows unregulated cell growth in tissues and bone. The mutated AKT1 gene that causes Proteus syndrome is only present in the cells of tissues that display the abnormal growth. Known as a mosaic, individuals with Proteus syndrome can have both normal functioning AKT1 genes and the mutated version, depending on what tissues are sampled. Because it is not present in every cell, positive identification based on this mutation alone can be difficult as many different samples may have to be taken.
Proteus syndrome arises as a spontaneous mutation during the embryonic development of the effected individual and is not an inherited trait. This disorder can affect individuals of any ethnicity and sex. Symptoms of this disorder usually develop after the first two years of life, although some individuals have been diagnosed shortly after birth.
The most famous individual thought to be afflicted with Proteus syndrome is Joseph Merrick, who was also known as The Elephant Man. Merrick died in London at the age of 27 in 1890 and his skeleton has been preserved in the Royal London Hospital. For decades, it was thought that Merrick had a different condition known as neurofibromatosis. Now, thanks to the great advances in genetics and technology, samples of Merrick’s skeleton will be tested for the presence of the mutated AKT1 gene which would give a positive diagnosis for Proteus syndrome.
Thanks to the findings of the mutation of the AKT1 gene in Proteus syndrome patients, new treatment options are in the future. Treatment for individuals with Proteus syndrome is based on the severity of the growths and the location of where they occur. Ways in which to stop or slow the growths using chemotherapy and surgical extraction of the tissues provides some help for the patient but does not cure the disorder. Patients with Proteus syndrome will continue to have symptoms of this syndrome for life.
