Cockayne syndrome are genetic conditions marked by severe growth delay, small head size, developmental delays, and intellectual disabilities.
Individuals with this disorder exhibit increased sensitivity to sunlight, significant tooth decay, vision problems, and hearing loss. Distinct facial features like a small chin, large ears, and slender nose may cause affected individuals to appear older than their actual age. These disorders encompass three forms: Cockayne syndrome type I, type II, and type III. Type I is the most common, where affected newborns initially appear normal but experience slowed growth within the first two years of life. They develop vision and hearing problems, along with neurological issues like muscle tone problems, difficulty walking, seizures, and behavioral challenges. Cockayne syndrome type II, or COFS syndrome, is the most severe variant, with symptoms manifesting at birth or during infancy. These infants are born small and often have eye abnormalities such as cataracts. They face substantial growth problems and severe developmental delays, being unable to speak, sit, or walk independently. Cockayne syndrome type III is the mildest form, with symptoms emerging later in childhood. While these children share some features with types I and II, their growth deficiency and developmental delays are comparatively less severe.
This group of conditions is caused by pathogenic (disease-causing) variants in the ERCC6 (Type B) or ERCC8 (Type A) gene and exhibits autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. The risk of being a carrier is based on a person’s ancestry or ethnic background.