The gene field of this packet is empty, so no specific genes are certified here, and the genetic basis is not detailed further in this report. According to expert review, the condition is inherited in an autosomal recessive manner, and the review reports that no clear genotype-phenotype correlations have been identified, although one study found that individuals with variants in one of the two genes discussed in the review appeared to have less severe manifestations at the time of diagnosis than those with variants in the other. The structured inheritance field in the packet is empty. The same review states that carriers are asymptomatic.

According to expert review, formal clinical diagnostic criteria originally proposed for type I were later revised and expanded, and a diagnostic scoring system based on clinical and imaging criteria has been proposed more recently. Because the condition is progressive, the clinical diagnosis is described as becoming more certain as additional manifestations evolve over time. The review lists major criteria of postnatal growth failure, and progressive microcephaly with neurologic dysfunction, with brain MRI showing white matter dysmyelination and cerebral and cerebellar atrophy. Minor criteria listed include cutaneous photosensitivity, demyelinating peripheral neuropathy diagnosed by nerve conduction testing, pigmentary retinopathy or cataracts, sensorineural hearing loss, dental anomalies, and the characteristic appearance of cachectic dwarfism with sunken eyes.

The review describes type I as suspected when both major criteria and at least three minor criteria are present in an older child, type II as suspected in infants with growth failure at birth and little postnatal growth or neurologic development, and type III as suspected in children or teenagers with short stature, mild neurologic impairment, and progressive ataxia. COFS syndrome is described as suspected when prenatal growth failure and congenital microcephaly occur with arthrogryposis and congenital cataracts or other structural eye defects. The review's differential diagnosis discussion notes that congenital anomalies of the face, limbs, heart, or viscera, recurrent infections, metabolic or neurologic crises, hematologic abnormality, and cancer of any kind point toward alternative diagnoses, and it lists several other growth-restriction, progeroid, and photosensitivity disorders as conditions with overlapping features.

According to expert review, no clinical practice guidelines for Cockayne syndrome have been published, and the review states that there is no cure. Management described there is supportive and multidisciplinary, aimed at quality of life, function, and reducing complications. Described measures include feeding support with gastrostomy tube placement in some cases for poor growth, physical therapy and home safety assessments for spasticity, standard ophthalmologic treatment with sunglasses for lens and retina protection, hearing aids and cochlear implants for hearing loss, intensive dental care for caries, and sunscreen use with limited sun exposure for photosensitivity. The review also describes early intervention programs, special education services, and individualized education plans for developmental delay and intellectual disability in the United States, and notes that practice varies by country.

The review additionally describes evaluations after diagnosis across growth, development, neurologic, eye, hearing, skin, dental, skeletal, kidney, liver, and cardiac systems, and periodic surveillance of nutritional status, vision, hearing, liver, kidney, and blood pressure. It lists excessive sun exposure among the circumstances it flags as harmful, and states that growth hormone treatment cannot be supported in the absence of safety and efficacy data. The packet lists no FDA-approved treatment for this condition. An orphan designation is recorded for a combination of D-mannitol and L-proline (sponsor DNage B.V.) for Cockayne syndrome; a designation is not an approval.

According to expert review, the condition progresses over time, and outlook varies by subtype. Type I is described as progressing throughout childhood, with death during the first or second decade (mean age 16 years). Type II and COFS syndrome are described as having almost no psychomotor development, with death usually in the first decade, though prolonged survival is possible in a few cases. Type III is described as progressing through childhood and adulthood, with long-term survival into adulthood. The review states that the phenotype forms a continuous spectrum and that intermediate presentations can occur. Individuals with type I or II are described as not known to reproduce, and no skin cancer predisposition is listed for any subtype.

According to expert review, no therapy has been proved useful for Cockayne syndrome, and the review notes that clinical trials may not exist for the disorder. The packet's research summary classifies 83 publications, with basic science and preclinical work as the dominant type, and notes the presence of gene therapy, biomarker, and recent trial-related publications. Specific trial records are not certified as current in this packet, so no study-level activity is described here. The packet lists patient organizations including the National Initiative for Cockayne Syndrome, Riaan Research Initiative Inc. (which has a registry), and The Cockayne Syndrome Foundation Inc.