Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0043346 (xeroderma pigmentosum)
 2,924 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cerebro-oculo-facio-skeletal (COFS) syndrome is a recessively inherited rapidly progressive neurologic disorder leading to brain atrophy, with calcifications, cataracts, microcornea, optic atrophy, progressive joint contractures, and growth failure. Cockayne syndrome (CS) is a recessively inherited neurodegenerative disorder characterized by low to normal birth weight, growth failure, brain dysmyelination with calcium deposits, cutaneous photosensitivity, pigmentary retinopathy and/or cataracts, and sensorineural hearing loss. Cultured CS cells are hypersensitive to UV radiation, because of impaired nucleotide-excision repair (NER) of UV-induced damage in actively transcribed DNA, whereas global genome NER is unaffected. The abnormalities in CS are caused by mutated CSA or CSB genes. Another class of patients with CS symptoms have mutations in the XPB, XPD, or XPG genes, which result in UV hypersensitivity as well as defective global NER; such patients may concurrently have clinical features of another NER syndrome, xeroderma pigmentosum (XP). Clinically observed similarities between COFS syndrome and CS have been followed by discoveries of cases of COFS syndrome that are associated with mutations in the XPG and CSB genes. Here we report the first involvement of the XPD gene in a new case of UV-sensitive COFS syndrome, with heterozygous substitutions-a R616W null mutation (previously seen in patients in XP complementation group D) and a unique D681N mutation-demonstrating that a third gene can be involved in COFS syndrome. We propose that COFS syndrome be included within the already known spectrum of NER disorders: XP, CS, and trichothiodystrophy. We predict that future patients with COFS syndrome will be found to have mutations in the CSA or XPB genes, and we document successful use of DNA repair for prenatal diagnosis in triplet and singleton pregnancies at risk for COFS syndrome. This result strongly underlines the need for screening of patients with COFS syndrome, for either UV sensitivity or DNA-repair abnormalities.
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PMID:Cerebro-oculo-facio-skeletal syndrome with a nucleotide excision-repair defect and a mutated XPD gene, with prenatal diagnosis in a triplet pregnancy. 1144 45

This is the first detailed description of the neuropathology of a patient with xeroderma pigmentosum/Cockayne syndrome complex (XP/CS). This 6-year-old boy's clinical course, followed from infancy to death, is compared with that of the eight other known cases of XP/CS. Normal at birth, he developed the cutaneous sun sensitivity of XP in infancy and the infantile CS phenotype in early childhood. He had the characteristic CS facies, cachexia, failure of somatic and brain growth, spasticity, ataxia, pigmentary retinopathy, hearing loss, mixed peripheral neuropathy, and myopathy. Like his clinical phenotype, the neuropathology was also that of CS despite an XPG genotype. His brain weighed 350 grams (considerably less than the expected weight at birth) and revealed hydrocephalus, tigroid-type demyelination, dystrophic calcification and widespread neuronal loss and gliosis with hyperchromatic glial and endothelial nuclei. Peripheral nerve showed myelinopathy with axonal degeneration, and skeletal muscle had mixed myopathic and neuropathic features. Ophthalmic pathology disclosed cataracts, iris and ciliary body atrophy, inner retinal atrophy and gliosis, retinal pigment epithelial atrophy, and optic nerve atrophy. Molecular studies, which have appeared elsewhere, do not provide full understanding of the pathophysiology of the postnatal growth failure, cachexia, precocious aging, selectivity of tissues affected (such as myelinated axons), and other manifestations of this devastating illness.
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PMID:Xeroderma pigmentosum/cockayne syndrome complex: first neuropathological study and review of eight other cases. 1176 81

We examined the clinical, molecular and genetic features of a 16-year-old boy (XP2GO) with xeroderma pigmentosum (XP) and progressive neurological symptoms. The parents are not consanguineous. Increased sun sensitivity led to the diagnosis of XP at 2 years of age and a strict UV protection scheme was implemented. Besides recurrent conjunctivitis and bilateral pterygium, only mild freckling was present on his lips. He shows absent deep tendon reflexes, progressive sensorineural deafness and progressive mental retardation. MRI shows diffuse frontal cerebral atrophy and dilated ventricles. Symptoms of trichothiodystrophy (brittle hair with a tiger-tail banding pattern on polarized microscopy) or Cockayne syndrome (cachectic dwarfism, cataracts, pigmentary retinopathy and spasticity) were absent. XP2GO fibroblasts showed reduced post-UV cell survival (D(37) = 3.8 J/m(2)), reduced nucleotide excision repair, reduced expression of XPD mRNA and an undetectable level of XPD protein. Mutational analysis of the XPD gene in XP2GO revealed two different mutations: a common p.Arg683Trp amino acid change (c.2047C>T) known to be associated with XP and a novel frameshift mutation c.2009delG (p.Gly670Alafs*39). The latter mutation potentially behaves as a null allele. While not preventing neurological degeneration, early diagnosis and rigorous sun protection can result in minimal skin disease without cancer in XP patients.
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PMID:Strict sun protection results in minimal skin changes in a patient with xeroderma pigmentosum and a novel c.2009delG mutation in XPD (ERCC2). 1863 29

Cockayne syndrome (CS) is a disorder characterized by a variety of clinical features including cachectic dwarfism, severe neurological manifestations including microcephaly and cognitive deficits, pigmentary retinopathy, cataracts, sensorineural deafness, and ambulatory and feeding difficulties, leading to death by 12 years of age on average. It is an autosomal recessive disorder, with a prevalence of approximately 2.5 per million. There are several phenotypes (1-3) and two complementation groups (CSA and CSB), and CS overlaps with xeroderma pigmentosum (XP). It has been considered a progeria, and many of the clinical features resemble accelerated aging. As such, the study of CS affords an opportunity to better understand the underlying mechanisms of aging. The molecular basis of CS has traditionally been ascribed to defects in transcription and transcription-coupled nucleotide excision repair (TC-NER). However, recent work suggests that defects in base excision DNA repair and mitochondrial functions may also play key roles. This opens up the possibility for molecular interventions in CS, and by extrapolation, possibly in aging.
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PMID:Cockayne syndrome: Clinical features, model systems and pathways. 2750 8