Kokkuyne’s syndrome is a hereditary disease with damage to the skin and its appendages, organs of vision, hearing, and impaired DNA repair.
Genetic classification
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- Syndrome Cockoyne type I (A) (216400, gene CKNl(CSA), 5pter-5qter, p)
- Cockchuin’s syndrome type II (B) (133540, gene ERCC6[CSB\, xp. 10, p) is included in the complementation group of xeroderma pigmentosum B
- Kokkuyne’s syndrome type III (C) (*No. 216411, p) is included in complementation group B of xeroderma pigmentosa. Cockkuin’s syndrome type IV (D) (126340, ERCC2, xp.19, p) is included in complementation group D of xeroderma pigmentosa
- Cockkuin’s syndrome type V (G) (133530, ERCC5, xp.13, p) is included in complementation group G of xeroderma pigmentosa.
Genetic aspects. The CSA and CSB genes code for proteins that interact with a subgroup of proteins in RNA polymerase 2, an enzyme involved in DNA excision repair. In contrast to xeroderma pigmentosa, which is also accompanied by increased susceptibility to UV exposure, there was no significant increase in the incidence of skin cancer. This suggests that the defect in Cockchuin syndrome is located in the repair system of transcribed (active) genes, without affecting the mechanism of complete genome repair.
Clinical picture
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- Dwarfism with disproportionately long limbs
- Increased susceptibility to sunlight
- Premature appearance of senile appearance (skin atrophy, skin pigmentation, scars on the skin,
sunken eyes)
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- Pigmentary degeneration of the retina
- optic nerve atrophy
- Retinal disinsertion
- Incomplete closure of the eyelids
- Anomalies of the outer ear
- Deafness
- Microcephaly
- Outcasts
- Flexion contractures of the joints
- Early development of vascular atherosclerosis
- Arterial hypertension
- Mental retardation
- Stem disorders characteristic of CNS demyelination.
Research methods
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- Laboratory data:
- proteinuria
- decrease in the level of thymus hormones
- abnormal myelination on sural nerve biopsy
- DNA excision repair disorder
- X-ray: brain calcifications.
ICD. Q87.1 Congenital malformation syndromes presenting predominantly with dwarfism
MIM
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- 216400 Cockcoyne syndrome type I
- 133540 Cockcoyne’s syndrome type II
- 216411 Kokkuyne syndrome type III
- 126340 Cockcoyne syndrome type IV
- 133530 Kokkäjn syndrome type V Literature. Cockayne EA: Inherited Abnormalities of the Skin and its Appendages. London: Oxford Univ. Press, 1933