Rare Immunology News

Disease Profile

Cohen syndrome

Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.


US Estimated

Europe Estimated

Age of onset






Autosomal dominant A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease.


Autosomal recessive Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype.


dominant X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.


recessive Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder.


Mitochondrial or multigenic Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.


Multigenic or multifactor Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.


Not applicable


Other names (AKA)

COH1; Pepper syndrome; Hypotonia, obesity, and prominent incisors


Congenital and Genetic Diseases; Endocrine Diseases; Eye diseases;


Cohen syndrome is a congenital (present since birth) condition that was first described in 1973 by Dr. M.M. Cohen, Jr. When the syndrome was first described, it was believed that its main features were obesity, hypotonia (low muscle tone), intellectual disabilities, distinctive facial features with prominent upper central teeth and abnormalities of the hands and feet. Since Cohen syndrome was first described, over 100 cases have been reported worldwide. It is now known that the signs and symptoms present in people with Cohen syndrome may vary considerably. Although the exact cause of Cohen syndrome is unknown, some people with the condition have been found to have mutations in a gene called COH1 (also referred to as VPS13B). When Cohen syndrome is found to be inherited in families, it follows an autosomal recessive pattern. No cure is currently available; however, treatment for Cohen syndrome is focused on improving or alleviating signs and symptoms as they arise.[1][2][3]


The signs and symptoms of Cohen syndrome may vary greatly from person to person. Some studies have suggested that a large number of people with Cohen syndrome have similar facial features regardless of ethnic background, including thick hair and eyebrows, long eyelashes, wave-shaped palpebral fissures, broad nasal tip, smooth or shortened philtrum, and hypotonic appearance.[3] 

Other findings that tend to be more common among almost all people with Cohen syndrome are listed below.[3]

  • Retinal dystrophy (a type of eye disorder affecting the retina, causing progressive vision loss)
  • Progressive high myopia (nearsightedness)
  • Acquired microcephaly (smaller than normal-sized head)
  • Non-progressive intellectual disability, global developmental delay
  • Hypotonia
  • Joint hyperextensibility (unusually large range of joint movement)

This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.

Medical Terms Other Names
Learn More:
100% of people have these symptoms
Close sighted
Near sighted
Near sightedness

[ more ]

80%-99% of people have these symptoms
Aplasia/Hypoplasia of the tongue
Long slender fingers
Spider fingers

[ more ]

Chorioretinal dystrophy
Downslanted palpebral fissures
Downward slanting of the opening between the eyelids
Gingival overgrowth
Gum enlargement
Global developmental delay
High, narrow palate
Narrow, high-arched roof of mouth
Narrow, highly arched roof of mouth

[ more ]

Hypoplasia of the maxilla
Decreased size of maxilla
Decreased size of upper jaw
Maxillary deficiency
Maxillary retrusion
Small maxilla
Small upper jaw
Small upper jaw bones
Upper jaw deficiency
Upper jaw retrusion

[ more ]

Hypoplasia of the zygomatic bone
Cheekbone underdevelopment
Decreased size of cheekbone
Underdevelopment of cheekbone

[ more ]

Intellectual disability
Mental deficiency
Mental retardation
Mental retardation, nonspecific

[ more ]

Long eyelashes
Increased length of eyelashes
Unusually long eyelashes

[ more ]

Low anterior hairline
Low frontal hairline
Low-set frontal hairline

[ more ]

Abnormally small skull
Decreased circumference of cranium
Decreased size of skull
Reduced head circumference
Small head circumference

[ more ]

Little lower jaw
Small jaw
Small lower jaw

[ more ]

Muscular hypotonia
Low or weak muscle tone
Neurological speech impairment
Speech disorder
Speech impairment
Speech impediment

[ more ]

Low blood neutrophil count
Low neutrophil count

[ more ]

Open mouth
Gaped jawed appearance
Gaped mouthed appearance
Slack jawed appearance

[ more ]

Prominent nasal bridge
Elevated nasal bridge
High nasal bridge
Prominent bridge of nose
Prominent nasal root
Protruding bridge of nose
Protruding nasal bridge

[ more ]

Reduced number of teeth
Decreased tooth count
Sandal gap
Gap between 1st and 2nd toes
Gap between first and second toe
Increased space between first and second toes
Sandal gap between first and second toes
Wide space between 1st, 2nd toes
Wide space between first and second toes
Wide-spaced big toe
Widely spaced 1st-2nd toes
Widely spaced first and second toes
Widened gap 1st-2nd toes
Widened gap first and second toe

[ more ]

Short philtrum
Slender toe
Narrow toe
Tapered finger
Tapered fingertips
Tapering fingers

[ more ]

Thick eyebrow
Bushy eyebrows
Dense eyebrow
Heavy eyebrows
Prominent eyebrows
Thick eyebrows

[ more ]

30%-79% of people have these symptoms
Abnormality of skin pigmentation
Abnormal pigmentation
Abnormal skin color
Abnormal skin pigmentation
Abnormality of pigmentation
Pigmentary changes
Pigmentary skin changes
Pigmentation anomaly

[ more ]

Cat cry
cat-like cry
Clinodactyly of the 5th finger
Permanent curving of the pinkie finger
Cubitus valgus
Outward turned elbows
Decreased fetal movement
Less than 10 fetal movements in 12 hours
Delayed puberty
Delayed pubertal development
Delayed pubertal growth
Pubertal delay

[ more ]

Failure to thrive in infancy
Faltering weight in infancy
Weight faltering in infancy

[ more ]

Feeding difficulties in infancy
Finger syndactyly
Genu valgum
Knock knees
Intrauterine growth retardation
Prenatal growth deficiency
Prenatal growth retardation

[ more ]

Joint hyperflexibility
Joints move beyond expected range of motion
Increased width of tooth
Narrow palm
Having too much body fat
Short stature
Decreased body height
Small stature

[ more ]

Thick hair
Increased hair density
Weak cry
5%-29% of people have these symptoms
Abnormality of retinal pigmentation
Abnormality of the hip bone
Abnormality of the hips
Aplasia/Hypoplasia of the earlobes
Absent/small ear lobes
Absent/underdeveloped ear lobes

[ more ]

Undescended testes
Undescended testis



The diagnosis of Cohen syndrome is based on the symptoms present in the patient, but because the symptoms vary greatly from person to person, no consensus diagnostic criteria exist. Genetic testing is available for COH1, the only gene known to be associated with Cohen syndrome. However, the rate at which mutations are detected via genetic testing varies by ethnicity. For example, the mutation detection rate in COH1 is higher among the Finnish and Old Amish compared to individuals of from other populations. [3]

Testing Resources

  • The Genetic Testing Registry (GTR) provides information about the genetic tests for this condition. The intended audience for the GTR is health care providers and researchers. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.


    There is no cure for Cohen syndrome. Treatment is focused on improving or alleviating the signs and symptoms in the patient. Typically, when a person is first diagnosed with Cohen syndrome, he or she will undergo an eye and blood examination. If vision problems are detected, early correction of the problems, usually with glasses, often leads to general improvement of cognitive skills. If neutropenia (a condition in which an abnormally low number of white blood cells called neutrophils are present, which may result in an increased risk for infections) is discovered when the blood is examined, treatment should be given. Follow-up should include annual eye exams and repeat testing of white blood cell count. Early intervention and physical, occupational, and speech therapy can address developmental delay, hypotonia, joint hyperextensibility, and motor clumsiness.[2][3]


    Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

    Organizations Supporting this Disease

      Learn more

      These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

      Where to Start

      • Genetics Home Reference (GHR) contains information on Cohen syndrome. This website is maintained by the National Library of Medicine.
      • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

        In-Depth Information

        • GeneReviews provides current, expert-authored, peer-reviewed, full-text articles describing the application of genetic testing to the diagnosis, management, and genetic counseling of patients with specific inherited conditions.
        • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
        • Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
        • Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
        • PubMed is a searchable database of medical literature and lists journal articles that discuss Cohen syndrome. Click on the link to view a sample search on this topic.


          1. Blachford SL. Cohen syndrome. Encyclopedia of Genetic Disorders. eNotes.com. 2013; https://www.enotes.com/genetic-disorders-encyclopedia/cohen-syndrome. Accessed 3/21/2013.
          2. García Ballesta C, Pérez Lajarin L, Cortés Lillo O. Cohen syndrome. Orphanet. 2004; https://www.orpha.net/data/patho/GB/uk-cohen.pdf. Accessed 3/21/2013.
          3. Falk MJ, Wang H, Traboulsi EI. Cohen Syndrome. GeneReviews. March 2011; https://www.ncbi.nlm.nih.gov/books/NBK1482/. Accessed 3/21/2013.

          Rare Immunology News