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BACKGROUND: Xeroderma pigmentosum group E (XP-E) is one of the least common forms of XP, a rare syndrome where patients are prone to develop skin cancer in exposed sunlight areas. XP-E patients are generally not diagnosed until they are adults due to the mild phenotype. CASE PRESENTATION: two XP-E siblings, female, 23 years, and male, 25 years, from a Brazilian consanguineous family carrying the novel missense pathogenic variant in DDB2 gene, NM_000107.3:c.1027G > C, associated with skin cancer early-onset and severe phenotype, as nodular melanoma in the cornea and in the ear. CONCLUSION: The assessment of genomic variant pathogenicity was a challenge since this family belongs to an underrepresented population in genomic databases. Given the scarcity of literature documenting XP-E cases and the challenges encountered in achieving an early diagnosis, this report emphasizes the imperative of sun protection measures in XP-E patients. Additionally, it highlights the detrimental impact of the COVID-19 pandemic on cancer diagnosis, leading to the manifestation of a severe phenotype in affected individuals.

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In central Brazil, in the municipality of Faina (state of Goiás), the small and isolated village of Araras comprises a genetic cluster of xeroderma pigmentosum (XP) patients. The high level of consanguinity and the geographical isolation gave rise to a high frequency of XP patients. Recently, two founder events were identified affecting that community, with two independent mutations at the POLH gene, c.764 + 1 G > A (intron 6) and c.907 C > T; p.Arg303* (exon 8). These deleterious mutations lead to the xeroderma pigmentosum variant syndrome (XP-V). Previous reports identified both mutations in other countries: the intron 6 mutation in six patients (four families) from Northern Spain (Basque Country and Cantabria) and the exon 8 mutation in two patients from different families in Europe, one of them from Kosovo. In order to investigate the ancestry of the XP patients and the age for these mutations at Araras, we generated genotyping information for 22 XP-V patients from Brazil (16), Spain (6) and Kosovo (1). The local genomic ancestry and the shared haplotype segments among the patients showed that the intron 6 mutation at Araras is associated with an Iberian genetic legacy. All patients from Goiás, homozygotes for intron 6 mutation, share with the Spanish patients identical-by-descent (IBD) genomic segments comprising the mutation. The entrance date for the Iberian haplotype at the village was calculated to be approximately 200 years old. This result is in agreement with the historical arrival of Iberian individuals at the Goiás state (BR). Patients from Goiás and the three families from Spain share 1.8 cM (family 14), 1.7 cM (family 15), and a more significant segment of 4.7 cM within family 13. On the other hand, the patients carrying the exon 8 mutation do not share any specific genetic segment, indicating an old genetic distance between them or even no common ancestry.

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Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by DNA repair defects that cause photophobia, sunlight-induced cancers, and neurodegeneration. Prevalence of germline mutations in the nucleotide excision repair gene XPA vary significantly in different populations. No Brazilian patients have been reported to carry a germline mutation in this gene. In this study, the germline mutational status of XPA was determined in Brazilian patients exhibiting major clinical features of XP syndrome. The study was conducted on 27 unrelated patients from select Brazilian families. A biallelic inactivating transition mutation c.619C>T (p.Arg207Ter) was identified in only one patient with a history of neurological impairment and mild skin abnormalities. These findings suggest that XP syndrome is rarely associated with inherited disease-causing XPA mutations in the Brazilian population. Additionally, this report demonstrates the effectiveness of genotype-phenotype correlation as a valuable tool to guide direct genetic screening.

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Estudo de revisão sobre xeroderma pigm en toso (XP), realizado por levantamento bibliográfico nas bases dedadas MEDLINE e LILACS. Trata-se de genodermatose rara, ocasionada por defeito no sistema de excisão e reparo de nucleotídeos (NER), que ocasiona dano celular após exposição solar. Caracteriza-se por alterações cutâneas, oftalmológicas, neurológicas, ósseas e grande associação com neoplasias. O diagnóstico é clínico, pode ser confirmado por teste de síntese anormal de DNA. Não há cura e o controle da patologia deve ser feito através de fotoproteção extrema, e em alguns casos pode-se fazer uso de retinóides para preveni-los

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O xeroderma pigmentoso é uma genodermatose caracterizada por um reparo inadequado de lesões do DNA, ocasionado pela radiação ultravioleta, com conseqüente desenvolvimento de alterações cutâneas, oftálmicas e neurológicas, além de alta incidência de melanomas em crianças. As alterações clínicas são progressivas e aumentam em número em proporção direta à exposição aos raios UV, obrigando os pacientes a estarem totalmente protegidos de qualquer exposição à luz solar. Os autores apresentam o tratamento clínico e as novas e promissoras abordagens terapêuticas e da geneterapia, bem como a classificação clínica dos grupos genéticos.

Xeroderma pigmentosum is a genodermotosis triggered by the inadequate repair of DNA lesions caused by ultraviolet radiation, with the subsequent development of ophthalmic, neurologic, and skin changes, as well as a high incidence of melanoma cases in children. Clinical changes have a progressive pattern, and skin lesions increase in number in the same proportion as UV exposure, forcing patients to protect themselves from any sunlight radiation. Medical treatment, along with the new and promising therapeutic approaches, including gene therapy, are presented in this paper, as well as the clinical classification of the genetic groups.

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Histopatholgoical analysis of cutaneous lesions in 195 patients with HIV/AIDS was carried out between 1989 to 1997 at tertiary level public hospital in Mumbai. 104/195 (53 per cent) cases showed infectious diseases which comprised of molluscum contagiosum (28), condyloma accuminata (18), verruca vulgaris (7), varicella zoster (5), syphilis (14), tuberculosis (13), donovanosis (4), leprosy (2), chancroid (2), bacillary angiomatosis (2), lymphogranuloma venercum (1), Norwegian scabies (3), leishmaniasis (2), demodicidosis (1), crytococcosis (1), tinea versicolor (1). In 12 (6 per cent) cases neoplasms were observed which included squamous cell carcinoma (9), basal cell carcinoma (2) and kaposi's sarcoma (1) case. The miscellaneous conditions were observed in 66(33.5 per cent) cases which comprised of psoriasis (21), papular urticaria (13), Reiter's disease (7) and eosinophilic folliculitis (6). The prevalence of cutaneous tuberculosis observed in this study is high as compared with western literature while the prevalence of kaposis's sarcoma is quite low as compared with reports from Africa, USA and United Kingdom.

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