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Khalat N, Messaoud O, Ben Rekaya M, Chargui M, Zghal M, Zendah B, Saqer N, Mokni M, Abdelhak S, Mohamed OA. First genetic characterization of Xeroderma pigmentosum in Libya: High frequency of XP-C founder mutation. Mol Genet Genomic Med 2023:e2158. [PMID: 36812379 DOI: 10.1002/mgg3.2158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 01/18/2023] [Accepted: 02/09/2023] [Indexed: 02/24/2023] Open
Abstract
BACKGROUND Xeroderma pigmentosum is an autosomal recessive disease characterized by a high sensitivity to UV radiations. The disease is clinically and genetically heterogeneous, thus making accurate early clinical diagnosis difficult. Although the disease is considered rare worldwide, previous studies have shown that it is more frequent in Maghreb countries. So far, no genetic study has been published on Libyan patients, except three reports limited to clinical descriptions. METHODS Our study, which represents the first genetic characterization of XP in Libya, was conducted on 14 unrelated families including 23 Libyan XP patients with a consanguinity rate of 93%. Blood samples were collected from 201 individuals including patients and their relatives. Patients were screened for founder mutations already described in Tunisia. RESULTS The two founder Maghreb XP mutations, XPA p.Arg228* associated with the neurological form and XPC p.Val548Alafs*25 in patients with only cutaneous manifestations, were homozygously identified. The latter was predominant (19 of 23 patients). In addition, another XPC homozygous mutation (p.Arg220*) has been identified in only one patient. For the remaining patient, the absence of founder XPA, XPC, XPD, and XPG mutations suggests mutational heterogeneity of XP in Libya. CONCLUSION Identification of common mutations with other Maghreb populations is in favor of a common ancestor in North-African populations.
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Affiliation(s)
| | - Olfa Messaoud
- Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, University Tunis El Manar, Tunis, Tunisia
| | - Mariem Ben Rekaya
- Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, University Tunis El Manar, Tunis, Tunisia
| | - Mariem Chargui
- Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, University Tunis El Manar, Tunis, Tunisia
| | - Mohamed Zghal
- Dermatology Department, Charles Nicolle Hospital, Tunis, Tunisia
| | - Bashir Zendah
- Dermatology Department, Medical Tripoli Centre (MTC), Tripoli, Libya
| | - Najat Saqer
- Dermatology Department, Central Tripoli Hospital, Tripoli, Libya
| | - Mourad Mokni
- Dermatology Department, La Rabta Hospital, Tunis, Tunisia
| | - Sonia Abdelhak
- Institut Pasteur de Tunis, Biomedical Genomics and Oncogenetics Laboratory, University Tunis El Manar, Tunis, Tunisia
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Abbassi M, Sayel H, Senhaji N, Trhanint S, Bay Bay H, Bouguenouch L, Mernisi FZ. Clinical and molecular characterization of Xeroderma pigmentosum in Moroccan population: a case series of 40 patients. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2022. [DOI: 10.1186/s43042-022-00368-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Abstract
Background
Xeroderma pigmentosum (XP) is a rare autosomal recessive skin disorder characterized by hyperpigmentation, premature skin aging, ocular and cutaneous photosensitivity with increased risk of skin tumors. XP is caused by mutations in DNA repair genes that protect cells from UV-induced DNA damage. The current study aims to investigate, on clinical and genetic basis, Moroccan XP patients. We explored by direct sequencing the involvement of the prevalent XPA and XPC genes mutations: nonsense mutation (c.682C>T, p.Arg228X) and a two-base-pair (2 bp) deletion (c.1643 1644delTG or p.Val548Ala fsX25), respectively, in 40 index cases from 37 unrelated families in Moroccan population.
Results
Early skin and ocular manifestations were detected with high rate of malignancy. Cutaneous lesions progressed to malignant skin tumor in 70% of cases. Ocular tumors were also observed in 11 patients including BCC in eight cases, SCC in three cases and melanoma in four cases. Among the 40 patients, there were 20 homozygous cases for the 2 bp deletion in the XPC gene and 9 homozygous cases carrying the nonsense XPA mutation.
Conclusion
These findings obtained in the present study revealed that the XPC gene mutation (c.1643 1644delTG, p.Val548AlafsX25) is the major cause of Xeroderma pigmentosum in our population. The c.682C>T (p.Arg228X) mutation is relatively associated with moderate phenotype in XP group A Moroccan families. This result will also contribute to improving the molecular diagnosis of XP disease and will have a significant impact on improving the care of Moroccan patients and their relatives.
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Albela H, Ngu LH, Leong KF. Xeroderma pigmentosum in a Malaysian child with identification of a novel homozygous nonsense mutation in XPC c.2167C>T. Int J Dermatol 2022; 61:e324-e326. [PMID: 35235204 DOI: 10.1111/ijd.16138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Revised: 12/19/2021] [Accepted: 02/07/2022] [Indexed: 11/29/2022]
Affiliation(s)
- Henrietta Albela
- Paediatric Dermatology Unit, Department of Paediatrics, Women & Children Hospital Kuala Lumpur, Malaysia
| | - Lock-Hock Ngu
- Genetics Department, Hospital Kuala Lumpur, Malaysia
| | - Kin Fon Leong
- Paediatric Dermatology Unit, Department of Paediatrics, Women & Children Hospital Kuala Lumpur, Malaysia
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Mezzi N, Messaoud O, Mkaouar R, Zitouna N, Romdhane S, Abdessalem G, Charfeddine C, Maazoul F, Ouerteni I, Hamdi Y, Zaouak A, Mrad R, Abdelhak S, Romdhane L. Spectrum of Genetic Diseases in Tunisia: Current Situation and Main Milestones Achieved. Genes (Basel) 2021; 12:1820. [PMID: 34828426 PMCID: PMC8617973 DOI: 10.3390/genes12111820] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 10/30/2021] [Accepted: 11/03/2021] [Indexed: 02/06/2023] Open
Abstract
Genetic diseases in Tunisia are a real public health problem given their chronicity and the lack of knowledge concerning their prevalence and etiology, and the high rates of consanguinity. Hence, we performed systematic reviews of the literature in order to provide a more recent spectrum of these disorders and to expose the challenges that still exist to tackle these kinds of diseases. A manual textual data mining was conducted using MeSH and PubMed databases. Collected data were classified according to the CIM-10 classification and the transmission mode. The spectrum of these diseases is estimated to be 589 entities. This suggests remarkable progress through the development of biomedical health research activities and building capacities. Sixty percent of the reported disorders are autosomal recessive, which could be explained by the high prevalence of endogamous mating. Congenital malformations (29.54%) are the major disease group, followed by metabolic diseases (22%). Sixty percent of the genetic diseases have a known molecular etiology. We also reported additional cases of comorbidity that seem to be a common phenomenon in our population. We also noticed that epidemiological data are scarce. Newborn and carrier screening was only limited to pilot projects for a few genetic diseases. Collected data are being integrated into a database under construction that will be a valuable decision-making tool. This study provides the current situation of genetic diseases in Tunisia and highlights their particularities. Early detection of the disease is important to initiate critical intervention and to reduce morbidity and mortality.
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Affiliation(s)
- Nessrine Mezzi
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
- Department of Biology, Faculty of Sciences of Bizerte, Université Tunis Carthage, Jarzouna 7021, Tunisia
| | - Olfa Messaoud
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Rahma Mkaouar
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Nadia Zitouna
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Safa Romdhane
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Ghaith Abdessalem
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Cherine Charfeddine
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
- High Institute of Biotechnology of Sidi Thabet, Biotechpole of Sidi Thabet, University of Manouba, Ariana 2080, Tunisia
| | - Faouzi Maazoul
- Department of Congenital and Hereditary Diseases, Charles Nicolle Hospital, Tunis 1002, Tunisia
| | - Ines Ouerteni
- Department of Congenital and Hereditary Diseases, Charles Nicolle Hospital, Tunis 1002, Tunisia
| | - Yosr Hamdi
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
- Laboratory of Human and Experimental Pathology, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Anissa Zaouak
- Department of Dermatology, Research Unit Genodermatosis and Cancer LR12SP03, Habib Thameur Hospital, Faculty of Medicine of Tunis, University of Tunis El Manar, Tunis 1002, Tunisia
| | - Ridha Mrad
- Department of Congenital and Hereditary Diseases, Charles Nicolle Hospital, Tunis 1002, Tunisia
| | - Sonia Abdelhak
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
| | - Lilia Romdhane
- Laboratory of Biomedical Genomics and Oncogenetics, Institut Pasteur de Tunis, Tunis 1002, Tunisia
- Department of Biology, Faculty of Sciences of Bizerte, Université Tunis Carthage, Jarzouna 7021, Tunisia
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Kouatcheu SD, Marko J, Tamura D, Khan SG, Lee CR, DiGiovanna JJ, Kraemer KH. Thyroid nodules in xeroderma pigmentosum patients: a feature of premature aging. J Endocrinol Invest 2021; 44:1475-1482. [PMID: 33155181 PMCID: PMC8096868 DOI: 10.1007/s40618-020-01451-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 10/12/2020] [Indexed: 01/02/2023]
Abstract
PURPOSE Xeroderma pigmentosum (XP) is an autosomal recessive disease with defective DNA repair, a markedly increased risk of skin cancer, and premature aging. Reports from North Africa have described thyroid nodules in XP patients, but thyroid nodule prevalence has never been determined in XP patients enrolled in our natural history study at the National Institutes of Health (NIH). METHODS We performed thyroid ultrasound examinations on all 29 XP patients examined from 2011 to 2019 and assessed nodule malignancy using the Thyroid Imaging Reporting and Data System. Thyroid nodule prevalence was also obtained from comparison cohorts. DNA sequencing was performed on thyroid tissue from XP patients who had surgery for thyroid cancer. RESULTS Thyroid nodules were identified in 18/29 XP patients (62%). The median age of patients with thyroid nodules in our XP cohort (20 years) was younger than that of three comparison groups: 36 years (California study-208 subjects), 48 years (Korean study-24,757 subjects), and 52 years (NIH-682 research subjects). Multiple (2-4) thyroid nodules were found in 12/18 (67%) of the patients with nodules. Autopsy examination revealed follicular adenomas in 4/8 (50%) additional XP patients. DNA sequencing revealed rare mutations in two other XP patients with papillary thyroid cancer. CONCLUSIONS XP patients have an increased incidence of thyroid nodules at an early age in comparison to the general population. These finding confirm another premature aging feature of XP.
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Affiliation(s)
- S D Kouatcheu
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA
- NIH Academy Enrichment Program, Bethesda, MD, USA
| | - J Marko
- Clinical Center, NIH, Bethesda, MD, USA
| | - D Tamura
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA
| | - S G Khan
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA
| | - C R Lee
- Laboratory of Pathology, CCR, NCI, NIH, Bethesda, MD, USA
| | - J J DiGiovanna
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA
| | - K H Kraemer
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research (CCR), National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, MD, USA.
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Clinical and Mutational Spectrum of Xeroderma Pigmentosum in Egypt: Identification of Six Novel Mutations and Implications for Ancestral Origins. Genes (Basel) 2021; 12:genes12020295. [PMID: 33672602 PMCID: PMC7924063 DOI: 10.3390/genes12020295] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 02/08/2021] [Accepted: 02/09/2021] [Indexed: 12/11/2022] Open
Abstract
Xeroderma pigmentosum is a rare autosomal recessive skin disorder characterized by freckle-like dry pigmented skin, photosensitivity, and photophobia. Skin and ocular symptoms are confined to sun exposed areas of the body. Patients have markedly increased risk for UV-induced skin, ocular, and oral cancers. Some patients develop neurodegenerative symptoms, including diminished tendon reflexes and microcephaly. In this study, we describe clinical and genetic findings of 36 XP patients from Egypt, a highly consanguineous population from North Africa. Thorough clinical evaluation followed by Sanger sequencing of XPA and XPC genes were done. Six novel and seven previously reported mutations were identified. Phenotype-genotype correlation was investigated. We report clinical and molecular findings consistent with previous reports of countries sharing common population structure, and geographical and historical backgrounds with implications on common ancestral origins and historical migration flows. Clinical and genetic profiling improves diagnosis, management, counselling, and implementation of future targeted therapies.
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Rizza ERH, DiGiovanna JJ, Khan SG, Tamura D, Jeskey JD, Kraemer KH. Xeroderma Pigmentosum: A Model for Human Premature Aging. J Invest Dermatol 2021; 141:976-984. [PMID: 33436302 DOI: 10.1016/j.jid.2020.11.012] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 11/14/2020] [Accepted: 11/16/2020] [Indexed: 12/19/2022]
Abstract
Aging results from intrinsic changes (chronologic) and damage from external exposures (extrinsic) on the human body. The skin is ideal to visually differentiate their unique features. Inherited diseases of DNA repair, such as xeroderma pigmentosum (XP), provide an excellent model for human aging due to the accelerated accumulation of DNA damage. Poikiloderma, atypical lentigines, and skin cancers, the primary cutaneous features of XP, occur in the general population but at a much older age. Patients with XP also exhibit ocular changes secondary to premature photoaging, including ocular surface tumors and pterygium. Internal manifestations of premature aging, including peripheral neuropathy, progressive sensorineural hearing loss, and neurodegeneration, are reported in 25% of patients with XP. Internal malignancies, such as lung cancer, CNS tumors, and leukemia and/or lymphoma, occur at a younger age in patients with XP, as do thyroid nodules. Premature ovarian failure is overrepresented among females with XP, occurring 20 years earlier than in the general population. Taken together, these clinical findings highlight the importance of DNA repair in maintaining genomic integrity. XP is a unique model of human premature aging, which is revealing new insights into aging mechanisms.
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Affiliation(s)
- Elizabeth R H Rizza
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - John J DiGiovanna
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Sikandar G Khan
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Deborah Tamura
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Jack D Jeskey
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA; Medical Research Scholar Program, National Institutes of Health, Bethesda, Maryland, USA
| | - Kenneth H Kraemer
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, USA.
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Paul D, Mu H, Tavakoli A, Dai Q, Chen X, Chakraborty S, He C, Ansari A, Broyde S, Min JH. Tethering-facilitated DNA 'opening' and complementary roles of β-hairpin motifs in the Rad4/XPC DNA damage sensor protein. Nucleic Acids Res 2020; 48:12348-12364. [PMID: 33119737 PMCID: PMC7708039 DOI: 10.1093/nar/gkaa909] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/28/2020] [Accepted: 10/02/2020] [Indexed: 01/01/2023] Open
Abstract
XPC/Rad4 initiates eukaryotic nucleotide excision repair on structurally diverse helix-destabilizing/distorting DNA lesions by selectively 'opening' these sites while rapidly diffusing along undamaged DNA. Previous structural studies showed that Rad4, when tethered to DNA, could also open undamaged DNA, suggesting a 'kinetic gating' mechanism whereby lesion discrimination relied on efficient opening versus diffusion. However, solution studies in support of such a mechanism were lacking and how 'opening' is brought about remained unclear. Here, we present crystal structures and fluorescence-based conformational analyses on tethered complexes, showing that Rad4 can indeed 'open' undamaged DNA in solution and that such 'opening' can largely occur without one or the other of the β-hairpin motifs in the BHD2 or BHD3 domains. Notably, the Rad4-bound 'open' DNA adopts multiple conformations in solution notwithstanding the DNA's original structure or the β-hairpins. Molecular dynamics simulations reveal compensatory roles of the β-hairpins, which may render robustness in dealing with and opening diverse lesions. Our study showcases how fluorescence-based studies can be used to obtain information complementary to ensemble structural studies. The tethering-facilitated DNA 'opening' of undamaged sites and the dynamic nature of 'open' DNA may shed light on how the protein functions within and beyond nucleotide excision repair in cells.
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Affiliation(s)
- Debamita Paul
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798, USA
| | - Hong Mu
- Department of Biology, New York University, New York, NY 10003, USA
| | - Amirrasoul Tavakoli
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798, USA
| | - Qing Dai
- Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA
| | - Xuejing Chen
- Department of Chemistry, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Sagnik Chakraborty
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Chuan He
- Department of Chemistry, The University of Chicago, Chicago, IL 60637, USA
- Department of Biochemistry and Molecular Biology, Howard Hughes Medical Institute, The University of Chicago, Chicago, IL 60637, USA
| | - Anjum Ansari
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
| | - Suse Broyde
- Department of Biology, New York University, New York, NY 10003, USA
| | - Jung-Hyun Min
- Department of Chemistry and Biochemistry, Baylor University, Waco, TX 76798, USA
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Genetic diversity and functional effect of common polymorphisms in genes involved in the first heterodimeric complex of the Nucleotide Excision Repair pathway. DNA Repair (Amst) 2019; 86:102770. [PMID: 31865061 DOI: 10.1016/j.dnarep.2019.102770] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 11/25/2019] [Accepted: 12/09/2019] [Indexed: 01/26/2023]
Abstract
Nucleotide excision repair is a multistep process that recognizes and eliminates a spectrum of DNA damages. Five proteins, namely XPC, RAD23, Centrin 2, DDB1 and DDB2 act as a heterodimeric complex at the early steps of the NER pathway and play a crucial role in the removal of DNA lesions. Several exonic mutations on genes coding for these proteins have been identified as associated with Xeroderma-pigmentosum (XP), a rare monogenic disorder. However, the role of regulatory polymorphisms in disease development and inter-ethnic diversity is still not well documented. Due to the high incidence rate of XP in Tunisia, we performed a genotyping analysis of 140 SNPs found on these 5 genes in a set of 135-subjects representing the general Tunisian-population. An inter-ethnic comparison based on the genotype frequency of these SNPs have been also conducted. For the most relevant variants, we performed a comprehensive assessment of their functional effects. Linkage disequilibrium and principal component analysis showed that the Tunisian-population is an admixed and intermediate population between Sub-Saharan Africans and Europeans. Using variable factor maps, we identified a list of 20 polymorphisms that contribute considerably to the inter-ethnic diversity of the NER complex. In-silico functional analysis showed that SNPs on XPC, DDB1 and DDB2 are associated with eQTLs mainly DDB2-rs10838681 that seems to decrease significantly the expression level of ACP2 (p = 6.1 × 10-26). Statistical analysis showed that the allelic frequency of DDB2-rs10838681 in Tunisia is significantly different from all other populations. Using rVarBase, we identified 5 variants on XPC, DDB1 and DDB2 that seem to alter the binding sites of several transcription factors considered as key players in DNA-repair pathways. Results presented in this study provide the first report on regulatory polymorphisms of the NER-complex genes in Tunisia. These results may also help to establish a baseline database for future association and functional studies.
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Xeroderma Pigmentosum: Ocular Findings in an Isolated Brazilian Group with an Identified Genetic Cluster. J Ophthalmol 2019; 2019:4818162. [PMID: 31781376 PMCID: PMC6875256 DOI: 10.1155/2019/4818162] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 08/19/2019] [Accepted: 09/30/2019] [Indexed: 01/01/2023] Open
Abstract
Purpose Xeroderma pigmentosum (XP) is a rare autosomal recessive genetic disorder characterized by increased susceptibility to UV radiation- (UVR-) induced skin pigmentation, skin cancers, ocular surface disease, and, in some patients, sunburn and neurological degeneration. Eight different genes are affected, and the prevalence of the disease differs across the world. The present study describes the main ophthalmologic features and symptoms in patients with XP in this case series. Methods Patients were examined consecutively at the University Hospital of the Federal University of Goias between January 2016 and June 2018. All patients underwent ophthalmologic examination and were asked about their ophthalmological history and the presence of ocular symptoms. Results Twenty-one patients with genetic confirmation were evaluated. The genetic variants XPV and XPC were detected in the patients. The most prevalent findings include eyelid changes, observed in 80.9% of the patients, and ocular surface changes as punctate keratopathy, occurring in 16 patients (76.2%), corneal neovascularization, and corneal opacities. Six patients (28.5%) presented corneoconjunctival tumor. More than half of patients had previous history of treatment of ocular neoplasia. Ocular burning was the most reported symptom. Conclusions The ocular characteristics identified in this study corroborate the existing literature, mainly related to the surface. Concerning the XP variant and the gravity of ocular signs, XPC has earlier and more severe symptoms than XPV. Due to their relative rarity, publications of XP cases are important to understand the possible damages caused by the disease in the eyes and surrounding area.
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Elloumi-Zghal H, Chaabouni Bouhamed H. Genetics and genomic medicine in Tunisia. Mol Genet Genomic Med 2018; 6:134-159. [PMID: 29663716 PMCID: PMC5902400 DOI: 10.1002/mgg3.392] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 03/07/2018] [Indexed: 01/19/2023] Open
Abstract
Genetics and genomic medicine in Tunisia.
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Ben Rekaya M, Naouali C, Messaoud O, Jones M, Bouyacoub Y, Nagara M, Pippucci T, Jmel H, Chargui M, Jerbi M, Alibi M, Dallali H, Bashamboo A, McElreavey K, Romeo G, Barakat A, Zghal M, Yacoub-Youssef H, Abdelhak S. Whole Exome Sequencing allows the identification of two novel groups of Xeroderma pigmentosum in Tunisia, XP-D and XP-E: Impact on molecular diagnosis. J Dermatol Sci 2018; 89:172-180. [DOI: 10.1016/j.jdermsci.2017.10.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Revised: 08/02/2017] [Accepted: 10/31/2017] [Indexed: 12/17/2022]
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Diagnosis of Xeroderma Pigmentosum Groups A and C by Detection of Two Prevalent Mutations in West Algerian Population: A Rapid Genotyping Tool for the Frequent XPC Mutation c.1643_1644delTG. BIOMED RESEARCH INTERNATIONAL 2016; 2016:2180946. [PMID: 27413738 PMCID: PMC4931069 DOI: 10.1155/2016/2180946] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 11/13/2015] [Accepted: 01/28/2016] [Indexed: 11/18/2022]
Abstract
Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder. Considering that XP patients have a defect of the nucleotide excision repair (NER) pathway which enables them to repair DNA damage caused by UV light, they have an increased risk of developing skin and eyes cancers. In the present study, we investigated the involvement of the prevalent XPA and XPC genes mutations—nonsense mutation (c.682C>T, p.Arg228X) and a two-base-pair (2 bp) deletion (c.1643_1644delTG or p.Val548Ala fsX25), respectively—in 19 index cases from 19 unrelated families in the West of Algeria. For the genetic diagnosis of XPA gene, we proceeded to PCR-RFLP. For the XPC gene, we validated a routine analysis which includes a specific amplification of a short region surrounding the 2 bp deletion using a fluorescent primer and fragment sizing (GeneScan size) on a sequencing gel. Among the 19 index cases, there were 17 homozygous patients for the 2 bp deletion in the XPC gene and 2 homozygous patients carrying the nonsense XPA mutation. Finally, XPC appears to be the major disease-causing gene concerning xeroderma pigmentosum in North Africa. The use of fragment sizing is the simplest method to analyze this 2 bp deletion for the DNA samples coming from countries where the mutation c.1643_1644delTG of XPC gene is prevalent.
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