Cohen syndrome, named for one of the researchers who initially described it in the 1970s, is a genetic disorder associated with intellectual disabilities, unusual facial features, and poor muscle tone. It is a genetic recessive, involving anomalies with an area of the eighth chromosome. People must inherit two copies of the defective chromosome in order to express this condition, and it can be quite variable in presentation because a complex of genes is involved. Treatment is focused on providing appropriate supportive care to keep patients comfortable.
Early signs of Cohen syndrome are often evident shortly after birth. The head tends to be smaller than usual and will continue to retain a small size as the child develops, while the space between the upper lip and the nose is shorter than usual, causing the baby to have an open-mouthed expression. When the teeth develop, the front incisors are often large. The hands and feet may also be smaller in size than expected, and many children with this condition have vision problems.
In addition to poor muscle tone, people with Cohen syndrome often have a condition called joint hypermobility, where the joints are more flexible than usual. This can expose them to the risk of joint strain and damage caused by flexing the joints too far and injuring neighboring ligaments and muscles. As people with this condition grow older, they often develop obesity in the torso, with the limbs remaining normally sized, and many have a friendly, outgoing disposition.
Cohen syndrome is usually associated with intellectual disability, and this may vary in severity. Some people with this condition have a limited capacity for learning and may not be able to grasp complex concepts, develop language skills, and live independently. Others may have more mild learning delays and difficulty learning, requiring some personal assistance but potentially being able to live on their own. Cohen syndrome can also be linked with seizures, and these may cause brain damage in the long term.
Also known as Pepper syndrome, this condition is rare. If both parents are carriers, there is a 25% chance of having a child with the condition, and the intensity of the symptoms is hard to predict. The varying presentation can also make it hard to diagnose without genetic sequencing and detailed observation of the patient. People concerned about the risks of passing on genetic diseases can meet with a genetic counselor to discuss their concerns and get advice on how to proceed.