[Cockayne Syndrome].

Cockayne syndrome (CS) is an autosomal recessive disorder characterized by severe photosensitive genodermatosis that is associated with premature aging caused by defects in the UV-induced DNA damage repair system, particularly the transcription-coupled nucleotide excision repair. The clinical features of CS include photosensitivity, a characteristic senile face, significant developmental abnormalities, such as short stature, underweight, and microcephaly, progressive cachexia, severe visual impairment, and sensorineural deafness. CS is clinically classified into type I (classical type), type II (congenital or severe type) and type III (late-onset or adult-onset type). Additionally, there exists a rare form of xerodema pigmentosum-Cockayne syndrome (XP/CS) complex. The incidence of CS is 2.7 in 1,000,000 individuals in Japan and 90% of the cases are type I. Unlike XP, in CS, skin cancer is not known to occur in areas of skin exposed to sunlight. However, we observed a case where solar keratosis developed in adult-onset CS patients (CS type III) with a pathological mutation in the CSB gene. In XP/CS, patients easily develop skin cancer from early childhood in areas of the skin exposed to sunlight.

Xeroderma pigmentosum group E and DDB2, a smaller subunit of damage-specific DNA binding protein: proposed classification of xeroderma pigmentosum, Cockayne syndrome, and ultraviolet-sensitive syndrome.

Xeroderma pigmentosum is a rare photosensitive syndrome that comprises eight different genetic diseases (A to G; variant (V)). Although genotype-phenotype correlations have been evaluated in most XP groups, the relationship between the E subgroup of xeroderma pigmentosum (XP-E) and damage-specific DNA binding protein (DDB) still remained a mystery. Recent studies have provided new insight for XP-E and the role(s) of DDB2, a smaller subunit of DDB. Reclassification studies have confirmed that mutations in DDB2 give rise to XP-E. The mouse model of XP-E demonstrated that DDB2 was well conserved between mouse and human and was critical in controlling proper cell-survival through regulating the tumor suppressor p53-mediated responses after ultraviolet (UV)-irradiation: i.e. defective DDB2 causes the resistance to cell-killing by UV-irradiation due to decreased p53-mediated apoptosis. These phenotypes are unique to XP-E because other XP groups show normal (XP-V) or hypersensitivity (XP-A, B, C, D, F, and G) to UV-irradiation. Thus XP-E is defined as a skin cancer prone disease with unique resistance to UV-irradiation.

Síndrome de Cockayne: tratamiento y rehabilitación. A propósito de un caso / Cockayne syndrome: treatment and rehabilitation. Based on one case

El síndrome de Cockayne es una extraña enfermedad autosómica recesiva caracterizada por retraso psicomotor y del crecimiento, deterioro neurológico progresivo, fotosensibilidad, alteraciones oftalmológicas, sordera neurosensorial, imágenes patológicas de calcificaciones y leucodistrofia en el sistema nervioso central, con desmielinización segmentaria en el sistema nervioso periférico. Presentamos el caso clínico de un paciente con síndrome de Cockayne de 11 años de edad, en el que se aprecia un cuadro abigarrado con retraso psicomotor y del crecimiento, ataxia, alteraciones del tono muscular, ortopédicas, sensoriales y del lenguaje. Describimos los tratamientos empleados, incluido un programa de rehabilitación integral individualizado, cuyo objetivo es mejorar la calidad de vida del paciente

Cockayne syndrome is a rare autosomal recessive disease characterized by physical and psychomotor retardation, progressive neurological disfunction, photosensitivity, ophthalmological abnormalities, neurosensorial deafness and other pathologic features such as leucodistrophy and calcifications in the central nervous system with segmental demyelination in the peripheral nervous system. In this work we report a clinical case of an eleven years old patient with Cockayne syndrome. This patient presents a mixed picture with growth and psychomotor retardation, ataxia, muscle tone alterations, orthopedic problems, sensorial disfunctions and speech problems. We describe the therapies used, including an individualized complete Rehabilitation program in order to improve the patient quality of life

Reduced RNA polymerase II transcription in intact and permeabilized Cockayne syndrome group B cells.

Cockayne syndrome (CS) is characterized by increased photosensitivity, growth retardation, and neurological and skeletal abnormalities. The recovery of RNA synthesis is abnormally delayed in CS cells after exposure to UV radiation. Gene-specific repair studies have shown a defect in the transcription-coupled repair (TCR) of active genes in CS cells from genetic complementation groups A and B (CS-A and CS-B). We have analyzed transcription in vivo in intact and permeabilized CS-B cells. Uridine pulse labeling in intact CS-B fibroblasts and lymphoblasts shows a reduction of approximately 50% compared with various normal cells and with cells from a patient with xeroderma pigmentosum (XP) group A. In permeabilized CS-B cells transcription in chromatin isolated under physiological conditions is reduced to about 50% of that in normal chromatin and there is a marked reduction in fluorescence intensity in transcription sites in interphase nuclei. Transcription in CS-B cells is sensitive to alpha-amanitin, suggesting that it is RNA polymerase II-dependent. The reduced transcription in CS-B cells is complemented in chromatin by the addition of normal cell extract, and in intact cells by transfection with the CSB gene. CS-B may be a primary transcription deficiency.

MRI in Cockayne syndrome type I.

MRI findings are reported from two patients with Cockayne syndrome (CS) type I, aged 11 and 37 years. Changes were compatible with diffuse white matter hypomyelination. Basal ganglia calcification was present in both, marked cerebellar atrophy in the older patient. MRI may support the diagnosis of CS in the appropriate clinical context. The view that CS is a dysmyelinating disorder is further substantiated.