Patients with Cohen syndrome very frequently exhibit abnormal eyelash and eyelid morphology, teeth abnormalities, lingual aplasia or hypoplasia, arachnodactyly, chorioretinal dystrophy, downslanted palpebral fissures, gingival overgrowth, global developmental delay, a high and narrow palate, maxillary hypoplasia, zygomatic bone hypoplasia, hypotonia, intellectual disability, long eyelashes, low anterior hairline, microcephaly, micrognathia, myopia, neurological speech impairment, neutropenia, open mouth, prominent nasal bridge, sandal gap, short philtrum, slender toes, tapered fingers, and thick eyebrows.

Some other frequently observed symptoms include abnormal skin pigmentation, cat cry, clinodactyly, cubitus valgus, decreased fetal movement, delayed puberty, failure to thrive during infancy, feeding difficulties during infancy, syndactyly, genu valgum, intrauterine growth retardation, joint hyperflexibility, macrodontia, narrow palm, obesity, short stature, thick hair, and a weak cry.

Ocular complications, though rare, are listed as optic atrophy, microphthalmia, pigmentary chorioretinitis, hemeralopia (decreased vision in bright light), myopia, strabismus, nystagmus and iris/retinal coloboma.

Those who have this disease may benefit from early exposure to speech, physical, and occupational therapy to correct symptoms such as joint overflexibility, developmental delays, hypotonia, and motor clumsiness.

[8] Diagnosis may potentially be delayed due to the lack of a definitive molecular test as well as the clinical variability of published case reports.

[12] Many people who have Cohen syndrome also have neutropenia which is a condition in which an individual has an abnormally low number of white blood cells called neutrophils.