Menkes syndrome, also called Menkes disease or kinky hair disease, is a genetic disorder causing copper deficiency. It is a recessive, sex-linked disorder on the X chromosome, meaning that men are more likely to develop it than women, while women are more likely to be asymptomatic carriers. Women can only inherit the disorder if both parents carry the defective gene, while only one copy of the defective gene is necessary for a male to be born with the disorder. Menkes syndrome is fairly rare, affecting about one in every 300,000 people.
Menkes syndrome is caused by a mutation in the ATP7A gene, which is responsible for making a protein that regulates the distribution of copper in the body. As a result of the mutation, some organs, notably the small intestine and kidney, have abnormally high copper levels, while others have dangerously low levels of copper. The body requires copper in order to produce a number of enzymes essential to a healthy metabolism.
Symptoms of Menkes syndrome are typically present from infancy. They can include premature birth, abnormally low weight or body temperature, sparse and wiry hair, stunted growth, weak muscles and bones, mental retardation or developmental impairment, neurodegeneration, damaged arteries in the brain, sagging facial features or pudgy cheeks, and seizures. The disease can also cause the metaphysis, the portion of long bones in which the growth plates are located, to widen. Babies with Menkes syndrome are often irritable and difficult to feed. The most well known symptom of the disorder, which gives it the colloquial name of kinky hair disease, is silvery or colorless, brittle, and coarse hair.
In a milder form of Menkes syndrome, called occipital horn syndrome, calcium deposits at the base of the skull, loose skin and joints, and coarse hair begin to appear during childhood. The deposits on the skull grow over the occipital bone and are called occipital horns. Occipital horn syndrome can also cause deformities of the elbow, clavicles, hips and pelvis, and dislocation of the head of the radius or elbow.
There is no cure for Menkes syndrome, so treatment is focused on addressing the symptoms as needed. The main form of treatment is copper replacement, as the majority of symptoms are directly caused by copper deficiency. It is best to begin this treatment as early as possible. Copper supplements are injected either intravenously, into a vein, or subcutaneously, under the skin. Babies with Menkes syndrome usually live for only a few years.