What Is Cohen Syndrome? Cohen syndrome, caused by mutations in the VPS13B gene, is an inherited condition that affects motor skills, mental development, and behavior. Infants with the condition grow slowly and do not gain weight at the normal rate. They may have a smaller-than-expected head size (microcephaly) and decreased muscle tone (hypotonia) with unusually flexible joints. Infants can feel floppy, like a rag doll, when lifted, and cannot control their heads. Over time, they have difficulty learning to roll over, sit up, crawl, and walk. Beginning in late childhood, people with Cohen syndrome may begin to put on weight in the torso. Without intervention, they can become obese, although their arms and legs remain slender. Patients with Cohen syndrome have distinct facial features. People with Cohen syndrome show moderate-to-severe intellectual and motor disability that remain constant and do not become progressively worse over time. They are prone to frequent and potentially severe infections because they have a lower-than-average level of certain infection-fighting white blood cells (neutropenia). Cohen syndrome generally causes severe, progressive vision problems, notably extreme nearsightedness and degeneration of the retina. People with the condition often become functionally, if not entirely, blind. They also tend to be unusually friendly and cheerful, even towards strangers. As a result, parents must be extra vigilant about their child's personal safety. How Common Is Cohen Syndrome? The exact prevalence of Cohen syndrome is unknown. It has been reported in fewer than 1000 people worldwide, although more cases likely exist. It is most common in a small Amish community in Ohio, where it affects an estimated 1 in 500 people. It is also more common in Finland. How Is Cohen Syndrome Treated? There is no cure for Cohen syndrome, but early intervention with physical, occupational, and speech therapy can address symptoms like joint laxity, clumsiness, and developmental delays. Children with nearsightedness need glasses, while those with retinal degeneration benefit from training for the visually impaired. In order to prevent recurrent infections, people with Cohen syndrome should be monitored throughout their lives for a low white blood cell count. What Is the Prognosis for a Person with Cohen Syndrome? The exact effect of Cohen syndrome on one's lifespan is unclear. Some people with the disease are known to be alive in their fifties. Other names forCohen syndrome Cohen syndrome Hypotonia, obesity, and prominent incisors Norio syndrome Pepper syndrome References Budisteanu et al., 2010, Maedica, 5(1):56-61, PMID: 21977120 OMIM: Online Mendelian Inheritance in Man, OMIM , 2016, https://www.omim.org/entry/216550 Wang et al., 2016, https://www.ncbi.nlm.nih.gov/books/NBK1482/ Resources The Arc A non-profit organization focused on developing and improving support and services for people with intellectual and developmental disabilities. National Organization for Rare Disorders (NORD) - Cohen syndrome A federation of health organizations dedicated to helping people with rare diseases through education, advocacy, support, and research. Address: 55 Kenosia Avenue Danbury, CT 06810 Phone: 203-744-0100 Genetics Home Reference- Cohen syndrome Explanations of an extensive number of genetic diseases written by the U.S. government's National Institutes of Health. Cohen Syndrome Association The Cohen Syndrome Association was founded by parents to raise awareness of this disease, with the goal of educating parents and professionals to assure earlier diagnosis and medical interventions.