1
|
Mohammadi Chermahini Z, Salehi M, Gheissari A, Ahmadi Beni F, Khosravian F, Kazemi M. CTNS Mutations Causing Autosomal Recessive Cystinosis in a Subset of Iranian Population: Report of Two New Variants. Adv Biomed Res 2024; 13:2. [PMID: 38525388 PMCID: PMC10958734 DOI: 10.4103/abr.abr_149_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 07/25/2023] [Accepted: 07/29/2023] [Indexed: 03/26/2024] Open
Abstract
Background Nephropathic cystinosis (NC) is an uncommon autosomal recessive disease with abnormality in lysosomal storage that appearances in patients with mutations in the CTNS gene encoding a lysosomal transporter cystinosin. Disrupted function of this transporter is followed by accumulation of cysteine crystals in cells of many various organs. This study aimed to investigate the mutations of the CTNS gene in 20 Iranian patients suffering from NC. Materials and Methods Twenty Iranian cystinosis patients referring to Imam Hossein Hospital of Isfahan were employed in this case-series study. After extraction of genomic DNA, the promoter and entire coding regions of CTNS were analysed using sanger sequencing in all patients. Gap-Polymerase Chain Reaction was used to detect 57 kb deletion in the CTNS gene. In silico study was performed to analyse variants. Results The large deletion was not seen in any NC patients. Molecular analysis which conducted to screen the CTNS gene of patients, identified eight different mutations, including two new mutations, c.971_972insC and c.956_956delA, which have not been reported before, and c.681G>A mutation, which was identified as a frequently founded mutation in the Middle East and was observed in 35% of patients. In this study, five other mutations including c.1015G>A, c.922G>A, c.323_323delA, c.433C>T, and c.18_21delGACT were also observed, which have been reported in previous studies. Conclusion The mutational spectrum in the Iranian patients is the same as previously reported mutations except that two new mutations were found. The present findings will present suggestions for regular molecular diagnosis of cystinosis in Iran.
Collapse
Affiliation(s)
- Zahra Mohammadi Chermahini
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
- Reproductive Sciences and Sexual Health Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
- Cellular, Molecular and Genetics Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mansoor Salehi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
- Cellular, Molecular and Genetics Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Alaleh Gheissari
- Department of Pediatrics, School of Medicine, Kidney Diseases Research Center, Imam Hossein Children’s Hospital, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Faeze Ahmadi Beni
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Farinaz Khosravian
- Cellular, Molecular and Genetics Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mohammad Kazemi
- Department of Genetics and Molecular Biology, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
- Reproductive Sciences and Sexual Health Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
| |
Collapse
|
2
|
Algasem R, Zainy N, Alsabban E, Almojalli H, Raza S, Ali T, Broering D, Rubaya N, Aleid H. The Clinical Manifestations and Disease Burden of Cystinosis in Saudi Arabia: A Single-Tertiary Center Experience. Cureus 2024; 16:e52662. [PMID: 38380220 PMCID: PMC10877213 DOI: 10.7759/cureus.52662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2024] [Indexed: 02/22/2024] Open
Abstract
BACKGROUND There is a lack of regional and local evidence that describes the nature of cystinosis, a multiorgan accumulation of cystine, and its extent of organ damage. Therefore, this study aimed to determine the outcomes of cystinosis in patients who were followed up at a large tertiary care hospital. METHODS Medical records of patients with cystinosis were retrospectively reviewed. Patients' baseline demographics, lab values, medications, comorbidities, and complications were collected and described. Univariable and multivariable logistics regression models were constructed to control for confounders and build prediction models. RESULTS In our cohort of 39 patients, the mean age was 13.8±9.9 years. Approximately 56.4% of the patients had stunted growth, and the mortality rate was 25.6%. Regarding complications, the majority of patients developed myopathy (79.5%), end-stage renal disease (ESRD) (74.4%), and hypothyroidism (71.8%). Age (odds ratio=1.14, 95% confidence interval (95% CI): 1.012, 1.285) and stunted growth (odds ratio=6.62, 95% CI: 1.024, 42.835) were found to be predictors of renal replacement therapy and renal transplantation, respectively (p<0.047). CONCLUSION This study on cystinosis patients reveals a high incidence of renal complications, with a significant mortality rate and common complications such as myopathy and ESRD. Age was found to be an independent risk factor for renal replacement therapy, while stunted growth predicted the need for transplantation. These findings underscore the urgency for early diagnosis, comprehensive treatment, and careful monitoring in managing cystinosis effectively.
Collapse
Affiliation(s)
- Reem Algasem
- Department of Pharmacy, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Nedaa Zainy
- Department of Pharmacy, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Essam Alsabban
- Department of Pediatric Nephrology, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Hamad Almojalli
- Department of Pediatric Transplant Nephrology, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Syed Raza
- Department of Kidney and Pancreas Transplant, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Tariq Ali
- Department of Kidney and Pancreas Transplant, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Deiter Broering
- Department of Kidney and Pancreas Transplant, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Nawal Rubaya
- Department of Kidney and Pancreas Transplant, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| | - Hassan Aleid
- Department of Kidney and Pancreas Transplant, King Faisal Specialist Hospital and Research Centre, Riyadh, SAU
| |
Collapse
|
3
|
Metabolomic Analyses to Identify Candidate Biomarkers of Cystinosis. Int J Mol Sci 2023; 24:ijms24032603. [PMID: 36768921 PMCID: PMC9916752 DOI: 10.3390/ijms24032603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/10/2023] [Accepted: 01/18/2023] [Indexed: 01/31/2023] Open
Abstract
Cystinosis is a rare, devastating hereditary disease secondary to recessive CTNS gene mutations. The most commonly used diagnostic method is confirmation of an elevated leukocyte cystine level; however, this method is expensive and difficult to perform. This study aimed to identify candidate biomarkers for the diagnosis and follow-up of cystinosis based on multiomics studies. The study included three groups: newly-diagnosed cystinosis patients (patient group, n = 14); cystinosis patients under treatment (treatment group, n = 19); and healthy controls (control group, n = 30). Plasma metabolomics analysis identified 10 metabolites as candidate biomarkers that differed between the patient and control groups [L-serine, taurine, lyxose, 4-trimethylammoniobutanoic acid, orotic acid, glutathione, PE(O-18:1(9Z)/0:0), 2-hydroxyphenyl acetic acid, acetyl-N-formil-5-metoxikinuramine, 3-indoxyl sulphate]. As compared to the healthy control group, in the treatment group, hypotaurine, phosphatidylethanolamine, N-acetyl-d-mannosamine, 3-indolacetic acid, p-cresol, phenylethylamine, 5-aminovaleric acid, glycine, creatinine, and saccharic acid levels were significantly higher, and the metabolites quinic acid, capric acid, lenticin, xanthotoxin, glucose-6-phosphate, taurine, uric acid, glyceric acid, alpha-D-glucosamine phosphate, and serine levels were significantly lower. Urinary metabolomic analysis clearly differentiated the patient group from the control group by means of higher allo-inositol, talose, glucose, 2-hydroxybutiric acid, cystine, pyruvic acid, valine, and phenylalanine levels, and lower metabolite (N-acetyl-L-glutamic acid, 3-aminopropionitrile, ribitol, hydroquinone, glucuronic acid, 3-phosphoglycerate, xanthine, creatinine, and 5-aminovaleric acid) levels in the patient group. Urine metabolites were also found to be significantly different in the treatment group than in the control group. Thus, this study identified candidate biomarkers that could be used for the diagnosis and follow-up of cystinosis.
Collapse
|
4
|
Bondue T, Kouraich A, Berlingerio SP, Veys K, Marie S, Alsaad KO, Al-Sabban E, Levtchenko E, van den Heuvel L. The Pitfall of White Blood Cell Cystine Measurement to Diagnose Juvenile Cystinosis. Int J Mol Sci 2023; 24:ijms24021253. [PMID: 36674769 PMCID: PMC9864853 DOI: 10.3390/ijms24021253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 01/05/2023] [Accepted: 01/05/2023] [Indexed: 01/11/2023] Open
Abstract
Cystinosis is an autosomal recessive lysosomal storage disease, caused by mutations in the CTNS gene, resulting in multi-organ cystine accumulation. Three forms of cystinosis are distinguished: infantile and juvenile nephropathic cystinosis affecting kidneys and other organs such as the eyes, endocrine system, muscles, and brain, and adult ocular cystinosis affecting only the eyes. Currently, elevated white blood cell (WBC) cystine content is the gold standard for the diagnosis of cystinosis. We present a patient with proteinuria at adolescent age and corneal cystine crystals, but only slightly elevated WBC cystine levels (1.31 ½ cystine/mg protein), precluding the diagnosis of nephropathic cystinosis. We demonstrate increased levels of cystine in skin fibroblasts and urine-derived kidney cells (proximal tubular epithelial cells and podocytes), that were higher than the values observed in the WBC and healthy control. CTNS gene analysis shows the presence of a homozygous missense mutation (c.590 A > G; p.Asn177Ser), previously described in the Arab population. Our observation underlines that low WBC cystine levels can be observed in patients with juvenile cystinosis, which may delay the diagnosis and timely administration of cysteamine. In such patients, the diagnosis can be confirmed by cystine measurement in slow-dividing cells and by molecular analysis of the CTNS gene.
Collapse
Affiliation(s)
- Tjessa Bondue
- Laboratory of Pediatric Nephrology, Department of Development and Regeneration, KU Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
| | - Anas Kouraich
- Laboratory of Pediatric Nephrology, Department of Development and Regeneration, KU Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
| | - Sante Princiero Berlingerio
- Laboratory of Pediatric Nephrology, Department of Development and Regeneration, KU Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
| | - Koenraad Veys
- Laboratory of Pediatric Nephrology, Department of Development and Regeneration, KU Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
- Department of Pediatrics, AZ Delta Campus Torhout, 8820 Torhout, Belgium
| | - Sandrine Marie
- Laboratory of Inherited Metabolic Diseases/Biochemical Genetics, Cliniques Universitaires Saint-Luc, UC Louvain, 1200 Brussels, Belgium
| | - Khaled O. Alsaad
- Section of Histopathology, Department of Pathology and Laboratory Medicine, King Faisal Specialist Hospital and Research Centre, Riyadh 11533, Saudi Arabia
| | - Essam Al-Sabban
- Section of Pediatric Nephrology, Department of Pediatrics, King Faisal Specialist Hospital and Research Centre, Riyadh 11533, Saudi Arabia
| | - Elena Levtchenko
- Laboratory of Pediatric Nephrology, Department of Development and Regeneration, KU Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
- Department of Pediatrics, University Hospitals Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
| | - Lambertus van den Heuvel
- Laboratory of Pediatric Nephrology, Department of Development and Regeneration, KU Leuven Campus Gasthuisberg, 3000 Leuven, Belgium
- Department of Pediatrics, Division of Pediatric Nephrology, Amalia Children’s Hospital, Radboud University Medical Center, HB-6524 Nijmegen, The Netherlands
- Correspondence:
| |
Collapse
|
5
|
El Younsi M, Trabelsi M, Ben Youssef S, Ouertani I, Hammi Y, Achour A, Maazoul F, Kharrat M, Gargah T, M'rad R. Clinical and genetic characteristics of Tunisian children with infantile nephropathic cystinosis. Pediatr Nephrol 2023; 38:119-129. [PMID: 35445972 DOI: 10.1007/s00467-022-05525-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 02/25/2022] [Accepted: 02/25/2022] [Indexed: 12/15/2022]
Abstract
BACKGROUND Nephropathic cystinosis is an autosomal recessive disease caused by a mutation in the CTNS gene which encodes cystinosin, a lysosomal cystine transporter. The spectrum of mutations in the CTNS gene is not well defined in the North African population. Here, we investigated twelve patients with nephropathic cystinosis belonging to eight Tunisian families in order to analyze the clinical and genetic characteristics of Tunisian children with infantile nephropathic cystinosis. METHODS Clinical data were collected retrospectively. Molecular analysis of the CTNS gene was performed by Sanger sequencing. RESULTS We describe a new splicing mutation c.971-1G > C in the homozygous state in 6/12 patients which seems to be a founder mutation. The reported deletion of 23nt c.771_793 Del (p.Gly258Serfs*30) was detected in a homozygous state in one patient and in a heterozygous compound state with the c.971-1G > C mutation in 3/12 patients. Two of 12 patients have a deletion of exons 4 and 5 of the CTNS gene. None of our patients had the most common 57-kb deletion. CONCLUSIONS The mutational spectrum in the Tunisian population is different from previously described populations. Thus, a molecular diagnostic strategy must be implemented in Tunisia, by targeting as a priority the common mutations described in this country. Such a strategy will allow a cost-effective diagnosis confirmation as well as early administration of treatment with oral cysteamine. A higher resolution version of the Graphical abstract is available as Supplementary information.
Collapse
Affiliation(s)
- Mariem El Younsi
- Laboratoire de Génétique Humaine, LR99ES10, Faculté de Médecine de Tunis, Université de Tunis El Manar, 1007, Tunis, Tunisia
| | - Médiha Trabelsi
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Sandra Ben Youssef
- Service de Pédiatrie Néphrologique Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Inès Ouertani
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Yousra Hammi
- Service de Pédiatrie Néphrologique Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Ahlem Achour
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Faouzi Maazoul
- Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Maher Kharrat
- Laboratoire de Génétique Humaine, LR99ES10, Faculté de Médecine de Tunis, Université de Tunis El Manar, 1007, Tunis, Tunisia
| | - Tahar Gargah
- Service de Pédiatrie Néphrologique Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia
| | - Ridha M'rad
- Laboratoire de Génétique Humaine, LR99ES10, Faculté de Médecine de Tunis, Université de Tunis El Manar, 1007, Tunis, Tunisia. .,Service des Maladies Congénitales et Héréditaires, Hôpital Charles Nicolle, Bab Souika, 1006, Tunis, Tunisia.
| |
Collapse
|
6
|
Gholami Yarahmadi S, Sarlaki F, Morovvati S. Cystinosis and two rare mutations in CTNS gene: two case reports. J Med Case Rep 2022; 16:181. [PMID: 35513889 PMCID: PMC9074344 DOI: 10.1186/s13256-022-03379-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Accepted: 03/18/2022] [Indexed: 11/22/2022] Open
Abstract
Background Cystinosis is an autosomal recessive disorder characterized by an accumulation of the amino acid cystine in lysosomes throughout the body. Cystinosis is an inherited disease resulting from the failure of lysosomal cystine transport. The responsible gene, Cystinosin, Lysosomal Cystine Transporter (CTNS), encodes the lysosomal cystine carrier cystinosin. Case presentation In this case report, we reviewed the genetic basis of cystinosis and investigated two Iranian cases affected by cystinosis, one of which revealed a rare mutation in the CTNS gene. Two patients, 9-year-old (patient A) and 11-year-old (patient B) symptomatic Iranian females with renal insufficiency, were diagnosed with cystinosis on the basis of their clinical features and laboratory tests. After genetic counseling, blood samples were obtained from the patients and their parents. Genomic Deoxyribonucleic Acid (DNA) was extracted from whole blood, and mutation analysis was performed using polymerase chain reaction and sequencing methods for all exons of the CTNS gene. At least 148 different pathogenic and deleterious mutations in the CTNS gene have been reported to date. Owing to our patient’s prominent clinical features of cystinosis, we carried out a targeted search for mutations in the CTNS gene. Conclusions This led us to confirm the existence of a homozygous DNA variation c.257_258deletionCT (p.Ser86PhefsTer38) in exon 6 of the gene in patient A and another homozygous DNA variation, c.323delA (p.Q108RfsTer10), in the same exon in patient B. As expected, the mentioned mutation existed in both her parents in a heterozygous state. Variations c.257_258delCT and c.323delA reported in three Iranian patients in the CTNS gene are frameshifts, and truncating mutations that affect product function result in relatively mild symptoms of cystinosis. The present finding confirms previous research and proves the importance of the association of this gene rare mutations with cystinosis. Since reported mutations are rare, their previous reports in Iranian patients indicate the high frequency of these mutations in our region.
Collapse
Affiliation(s)
- Sepideh Gholami Yarahmadi
- Department of Advanced Sciences and Technology, Islamic Azad University-Tehran Medical Sciences, Zargandeh, Shariati, Tehran, Iran
| | - Fatemeh Sarlaki
- Department of Clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Saeid Morovvati
- Department of Advanced Sciences and Technology, Islamic Azad University-Tehran Medical Sciences, Zargandeh, Shariati, Tehran, Iran.
| |
Collapse
|
7
|
Topaloglu R. Nephropathic cystinosis: an update on genetic conditioning. Pediatr Nephrol 2021; 36:1347-1352. [PMID: 32564281 DOI: 10.1007/s00467-020-04638-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 04/24/2020] [Accepted: 06/02/2020] [Indexed: 10/24/2022]
Abstract
Cystinosis is an autosomal recessive lysosomal storage disorder caused by CTNS gene mutations. The CTNS gene encodes the protein cystinosin, which transports free cystine from lysosomes to cytoplasm. In cases of cystinosin deficiency, free cystine accumulates in lysosomes and forms toxic crystals that lead to tissue and organ damage. Since CTNS gene mutations were first described, many variations have been identified that vary according to geographic region, although the phenotype remains the same. Cystinosis is a hereditary disease that can be treated with the cystine-depleting agent cysteamine. Cysteamine slows organ deterioration, but cannot treat renal Fanconi syndrome or prevent eventual kidney failure; therefore, novel treatment modalities for cystinosis are of great interest to researchers. The present review aims to highlight the geographic differences in cystinosis-specifically in terms of its genetic aspects, clinical features, management, and long-term complications.
Collapse
Affiliation(s)
- Rezan Topaloglu
- Department of Pediatric Nephrology, School of Medicine, Hacettepe University, Ankara, Turkey.
| |
Collapse
|
8
|
Najafi M, Tamandani DMK, Azarfar A, Bakey Z, Behjati F, Antony D, Schüle I, Sadeghi-Bojd S, Karimiani EG, Schmidts M. A 57 kB Genomic Deletion Causing CTNS Loss of Function Contributes to the CTNS Mutational Spectrum in the Middle East. Front Pediatr 2019; 7:89. [PMID: 30949462 PMCID: PMC6437787 DOI: 10.3389/fped.2019.00089] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2018] [Accepted: 02/28/2019] [Indexed: 12/03/2022] Open
Abstract
Background: Nephropathic Cystinosis, the most common cause of renal Fanconi syndrome, is a lysosomal transport disorder with an autosomal recessive inheritance pattern. A large number of mutations in CTNS have been identified as causative to date. A 57 kb deletion encompassing parts of CTNS is most commonly identified in Caucasians but this allele has not been identified in individuals of Eastern Mediterranean, Middle Eastern, Persian, or Arab origin to date. Methods and Results: Implementing whole exome sequencing (WES) in a consanguineous Iranian family, we identified this large deletion affecting CTNS in a patient initially presenting with hypokalemic metabolic alkalosis symptoms and considerable proteinuria. Conclusion: We show WES is a cost and time efficient genetic diagnostics modality to identify the underlying molecular pathology in Cystinosis individuals and provide a summary of all previously reported CTNS alleles in the Middle east population. Our work also highlights the importance to consider the 57-kb deletion as underlying genetic cause in non-European populations, including the Middle East. Limited diagnostic modalities for Cystinosis in developing countries could account for the lack of previously reported cases in these populations carrying this allele. Further, our findings emphasize the utility of WES to define genetic causes in clinically poorly defined phenotypes and demonstrate the requirement of Copy number variation (CNV) analysis of WES data.
Collapse
Affiliation(s)
- Maryam Najafi
- Genome Research Division, Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands.,Department of Biology, University of Sistan and Baluchestan, Zahedan, Iran
| | | | - Anoush Azarfar
- Department of Pediatrics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Zeineb Bakey
- Genome Research Division, Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands.,Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, University Hospital Freiburg, Freiburg University, Freiburg, Germany
| | - Farkhondeh Behjati
- Genetics Research Center, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran
| | - Dinu Antony
- Genome Research Division, Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands.,Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, University Hospital Freiburg, Freiburg University, Freiburg, Germany
| | - Isabel Schüle
- Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, University Hospital Freiburg, Freiburg University, Freiburg, Germany
| | - Simin Sadeghi-Bojd
- Children and Adolescents Health Research Center, Resistant Tuberculosis Institute, Zahedan University of Medical Sciences, Zahedan, Iran
| | - Ehsan Ghayoor Karimiani
- Next Generation Genetic Polyclinic, Mashhad, Iran.,Razavi Cancer Research, Razavi Hospital, Imam Reza International University, Mashhad, Iran
| | - Miriam Schmidts
- Genome Research Division, Human Genetics Department, Radboud University Medical Center Nijmegen and Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands.,Center for Pediatrics and Adolescent Medicine, Faculty of Medicine, University Hospital Freiburg, Freiburg University, Freiburg, Germany
| |
Collapse
|
9
|
Makuloluwa AK, Shams F. Cysteamine hydrochloride eye drop solution for the treatment of corneal cystine crystal deposits in patients with cystinosis: an evidence-based review. Clin Ophthalmol 2018; 12:227-236. [PMID: 29416314 PMCID: PMC5789046 DOI: 10.2147/opth.s133516] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Cystinosis is a rare, autosomal recessive disorder leading to defective transport of cystine out of lysosomes. Subsequent cystine crystal accumulation can occur in various tissues, including the ocular surface. This review explores the efficacy of cysteamine hydrochloride eye drops in the treatment of corneal cystine crystal accumulation and its safety profile.
Collapse
Affiliation(s)
| | - Fatemeh Shams
- Tennent Institute of Ophthalmology, Gartnavel General Hospital, Glasgow, UK
| |
Collapse
|
10
|
Topaloglu R, Gulhan B, İnözü M, Canpolat N, Yilmaz A, Noyan A, Dursun İ, Gökçe İ, Gürgöze MK, Akinci N, Baskin E, Serdaroğlu E, Demircioğlu Kiliç B, Yüksel S, Övünç Hacihamdioğlu D, Korkmaz E, Hayran M, Ozaltin F. The Clinical and Mutational Spectrum of Turkish Patients with Cystinosis. Clin J Am Soc Nephrol 2017; 12:1634-1641. [PMID: 28793998 PMCID: PMC5628704 DOI: 10.2215/cjn.00180117] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Accepted: 06/26/2017] [Indexed: 01/24/2023]
Abstract
BACKGROUND AND OBJECTIVES Infantile nephropathic cystinosis is a severe disease that occurs due to mutations in the cystinosis gene, and it is characterized by progressive dysfunction of multiple organs; >100 cystinosis gene mutations have been identified in multiple populations. Our study aimed to identify the clinical characteristics and spectrum of cystinosis gene mutations in Turkish pediatric patients with cystinosis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS We identified the clinical characteristics and spectrum of cystinosis gene mutations in Turkish patients with cystinosis in a multicenter registry that was established for data collection. The data were extracted from this registry and analyzed. RESULTS In total, 136 patients (75 men and 61 women) were enrolled in the study. The most common clinical findings were growth retardation, polyuria, and loss of appetite. None of the patients had the 57-kb deletion, but seven novel mutations were identified. The most common mutations identified were c.681G>A (p.Glu227Glu; 31%), c.1015G>A (p.Gly339Arg; 22%), and c.18_21 del (p.Thr7Phefs*7; 14%). These mutations were associated with earlier age of disease onset than the other mutations. To understand the effects of these allelic variants on clinical progression, the mutations were categorized into two major groups (missense versus deletion/duplication/splice site). Although patients with missense mutations had a better eGFR at the last follow-up visit, the difference was not significant. Patients in whom treatment began at age <2 years old had later onset of ESRD (P=0.02). Time to ESRD did not differ between the patients with group 1 and group 2 mutations. CONCLUSIONS The most common cystinosis gene mutations identified in Turkey were c.681G>A (p.Glu227Glu), c.1015G>A (p.Gly339Arg), and c.18_21 del (p.Thr7Phefs*7). Patients with less severe cystinosis gene mutations tend to have better kidney outcome.
Collapse
Affiliation(s)
- Rezan Topaloglu
- Due to the number of contributing authors, the affiliations are provided in the Supplemental Material
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Sadeghipour F, Basiratnia M, Derakhshan A, Fardaei M. Mutation analysis of the CTNS gene in Iranian patients with infantile nephropathic cystinosis: identification of two novel mutations. Hum Genome Var 2017; 4:17038. [PMID: 28983406 PMCID: PMC5628181 DOI: 10.1038/hgv.2017.38] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 07/07/2017] [Accepted: 07/09/2017] [Indexed: 12/02/2022] Open
Abstract
Nephropathic cystinosis is an inherited lysosomal transport disorder caused by mutations in the CTNS gene that encodes for a lysosomal membrane transporter, cystinosin. Dysfunction in this protein leads to cystine accumulation in the cells of different organs. The accumulation of cystine in the kidneys becomes apparent with renal tubular Fanconi syndrome between 6 and 12 months of age and leads to renal failure in the first decade of life. The aim of this study was to analyze the CTNS mutations in 20 Iranian patients, from 20 unrelated families, all of whom were afflicted with infantile nephropathic cystinosis. In these patients, seven different mutant alleles were found, including two new mutations, c.517T>C; p.Y173H and c.492_515del, that have not been previously reported. In addition, we observed that c.681G>A, the common Middle Eastern mutation, was the most common mutation in our patients. Moreover, a new minisatellite or variable number of tandem repeat marker (KX499495) was identified at the CTNS gene. Seven different alleles were found for this marker, and its allele frequency and heterozygosity degree were calculated in cystinosis patients and healthy individuals.
Collapse
Affiliation(s)
- Forough Sadeghipour
- Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mitra Basiratnia
- Department of Pediatric Nephrology, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Ali Derakhshan
- Department of Pediatric Nephrology, Namazi Hospital, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Majid Fardaei
- Department of Medical Genetics, Shiraz University of Medical Sciences, Shiraz, Iran.,Transgenic Technology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| |
Collapse
|
12
|
Doneray H, Aldahmesh M, Yilmaz G, Cinici E, Orbak Z. Infantile Nephropathic Cystinosis: A Novel CTNS Mutation. Eurasian J Med 2017. [PMID: 28638260 DOI: 10.5152/eurasianjmed.2017.17039] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Cystinosis is a rare autosomal recessive metabolic disorder characterized by the accumulation of cystine in lysosomes, which results from defects in the carrier-mediated transport protein encoded by the CTNS gene. Infantile nephropathic cystinosis (INC) is one of the major complications of cystinosis. It is characterized by findings of Fanconi's syndrome within the first year of life. Here we report two patients with INC presenting with signs of Fanconi's syndrome and describe a novel CTNS mutation.
Collapse
Affiliation(s)
- Hakan Doneray
- Department of Pediatrics, Atatürk University School of Medicine, Erzurum, Turkey
| | - Mohammed Aldahmesh
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia
| | - Gulsah Yilmaz
- Department of Pediatrics, Atatürk University School of Medicine, Erzurum, Turkey
| | - Emine Cinici
- Department of Ophtalmology, Erzurum Region Trainig and Research Hospital, Erzurum, Turkey
| | - Zerrin Orbak
- Department of Pediatrics, Atatürk University School of Medicine, Erzurum, Turkey
| |
Collapse
|
13
|
Deshpande AA, Ravichandran R, Bachhawat AK. Molecular Analysis of the CTNS Gene in Indians with Nephropathic Cystinosis. Indian J Pediatr 2017; 84:240-241. [PMID: 27885487 DOI: 10.1007/s12098-016-2257-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2016] [Accepted: 10/26/2016] [Indexed: 10/20/2022]
Affiliation(s)
- Anup Arunrao Deshpande
- Indian Institute of Science and Education Research, Sector 81, Knowledge City, SAS Nagar, Mohali, Punjab, India
| | | | - Anand Kumar Bachhawat
- Indian Institute of Science and Education Research, Sector 81, Knowledge City, SAS Nagar, Mohali, Punjab, India.
| |
Collapse
|
14
|
Ghazi F, Hosseini R, Akouchekian M, Teimourian S, Ataei Kachoei Z, Otukesh H, Gahl WA, Behnam B. CTNS molecular genetics profile in a Persian nephropathic cystinosis population. Nefrologia 2017; 37:301-310. [PMID: 28238446 DOI: 10.1016/j.nefro.2016.11.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Revised: 09/18/2016] [Accepted: 11/22/2016] [Indexed: 11/27/2022] Open
Abstract
PURPOSE In this report, we document the CTNS gene mutations of 28 Iranian patients with nephropathic cystinosis age 1-17 years. All presented initially with severe failure to thrive, polyuria, and polydipsia. METHODS Cystinosis was primarily diagnosed by a pediatric nephrologist and then referred to the Iran University of Medical Sciences genetics clinic for consultation and molecular analysis, which involved polymerase chain reaction (PCR) amplification to determine the presence or absence of the 57-kb founder deletion in CTNS, followed by direct sequencing of the coding exons of CTNS. RESULTS The common 57-kb deletion was not observed in any of the 28 Iranian patients. In 14 of 28 patients (50%), mutations were observed in exons 6 and 7. No mutation was detected in exon 5, and only one (3.6%) patient with cystinosis showed a previously reported 4-bp deletion in exon 3 of CTNS. Four patients (14.3%) had a previously reported mutation (c.969C>A; p.N323K) in exon 11, and five (18%) had novel homozygous deletions in exon 6 leading to premature truncation of the protein. These deletions included c.323delA; p.Q108RfsX10 in three individuals and c.257-258delCT; p.S86FfsX37 in two cases. Other frame-shift mutations were all novel homozygous single base pair deletion/insertions including one in CTNS exon 9 (c.661insT; p.V221CfsX6), and four (14.3%) in exon 4, i.e., c.92insG; p.V31GfsX28 in two and c.120delC; p.T40TfsX10 in two. In total, we identified eight previously reported mutations and eight novel mutations in our patients. The only detected splice site mutation (IVS3-2A>C) was associated with the insertion mutation in the exon 9. CONCLUSION This study, the first molecular genetic analysis of non-ethnic-specific Iranian nephropathic cystinosis patients, may provide guidance for molecular diagnostics of cystinosis in Iran.
Collapse
Affiliation(s)
- Farideh Ghazi
- Department of Medical Genetics and Molecular Biology, Faculty of Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - Rozita Hosseini
- Department of Pediatrics, Faculty of Medicine, Ali Asghar Children Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - Mansoureh Akouchekian
- Department of Medical Genetics and Molecular Biology, Faculty of Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - Shahram Teimourian
- Department of Medical Genetics and Molecular Biology, Faculty of Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - Zohreh Ataei Kachoei
- Department of Medical Genetics and Molecular Biology, Faculty of Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - Hassan Otukesh
- Department of Pediatrics, Faculty of Medicine, Ali Asghar Children Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran
| | - William A Gahl
- Section on Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD, USA; NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA
| | - Babak Behnam
- Department of Medical Genetics and Molecular Biology, Faculty of Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran; Department of Pediatrics, Faculty of Medicine, Ali Asghar Children Hospital, Iran University of Medical Sciences (IUMS), Tehran, Iran; Section on Human Biochemical Genetics, Medical Genetics Branch, National Human Genome Research Institute, NIH, Bethesda, MD, USA; NIH Undiagnosed Diseases Program, Common Fund, Office of the Director, NIH, Bethesda, MD, USA.
| |
Collapse
|
15
|
Cherqui S, Courtoy PJ. The renal Fanconi syndrome in cystinosis: pathogenic insights and therapeutic perspectives. Nat Rev Nephrol 2016; 13:115-131. [PMID: 27990015 DOI: 10.1038/nrneph.2016.182] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Cystinosis is an autosomal recessive metabolic disease that belongs to the family of lysosomal storage disorders. It is caused by a defect in the lysosomal cystine transporter, cystinosin, which results in an accumulation of cystine in all organs. Despite the ubiquitous expression of cystinosin, a renal Fanconi syndrome is often the first manifestation of cystinosis, usually presenting within the first year of life and characterized by the early and severe dysfunction of proximal tubule cells, highlighting the unique vulnerability of this cell type. The current therapy for cystinosis, cysteamine, facilitates lysosomal cystine clearance and greatly delays progression to kidney failure but is unable to correct the Fanconi syndrome. This Review summarizes decades of studies that have fostered a better understanding of the pathogenesis of the renal Fanconi syndrome associated with cystinosis. These studies have unraveled some of the early molecular changes that occur before the onset of tubular atrophy and identified a role for cystinosin beyond cystine transport, in endolysosomal trafficking and proteolysis, lysosomal clearance, autophagy and the regulation of energy balance. These studies have also led to the identification of new potential therapeutic targets and here, we outline the potential role of stem cell therapy for cystinosis and provide insights into the mechanism of haematopoietic stem cell-mediated kidney protection.
Collapse
Affiliation(s)
- Stephanie Cherqui
- Department of Pediatrics, Division of Genetics, University of California San Diego, 9500 Gilman Drive, MC 0734, La Jolla, California 92093-0734, USA
| | - Pierre J Courtoy
- Cell biology, de Duve Institute and Université catholique de Louvain, UCL-Brussels, 75 Avenue Hippocrate, B-1200 Brussels, Belgium
| |
Collapse
|
16
|
Doğan M, Bulan K, Kaba S, Cesur Y, Ceylaner S, Ustyol L. Cystinosis in Eastern Turkey. J Pediatr Endocrinol Metab 2016; 29:965-9. [PMID: 27269891 DOI: 10.1515/jpem-2014-0477] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 04/21/2016] [Indexed: 11/15/2022]
Abstract
BACKGROUND This study was conducted to investigate CTNS (cystinosin, lysosomal cystine transporter) gene mutations and the clinical spectrum of nephropathic cystinosis among patients diagnosed with the disease in a single center in Turkey. METHODS Patients' clinical and laboratory data were extracted from an electronic health registry. Molecular CTNS gene analysis was performed using either next-generation sequencing or Sanger sequencing. RESULTS Eleven patients (age range: 1.5-12 years) from nine families were identified. The presenting complaint was growth retardation in seven patients; polydipsia and polyuria in three patients; and vomiting in two patients. At presentation, electrolyte loss was noted in all patients, of which eight patients presented with metabolic acidosis, and three patients presented with metabolic alkalosis. All patients also presented with proteinuria and glucosuria, and four patients developed varying degrees of renal insufficiency, for which peritoneal dialysis was initiated in one patient. Cystine crystals were detected via ocular examination in one patient at presentation. No cystine crystals were detected among patients who underwent bone marrow aspiration. In the CTNS gene, a p.T7FX7 (c.18-21del4bp) mutation was detected in three patients, whereas a p.E227E (c.681 G>A) (homozygous) mutation was detected in eight patients. CONCLUSIONS We detected two distinct mutations, p.T7FX7 (c.18-21del4bp) and p.E227E (c.681 G>A) (homozygous), in the CTNS gene in 11 patients with cystinosis from the East Anatolian region of Turkey. Patients with a homozygous c.681 G>A (p.E227E) mutation are more likely to develop chronic renal failure and should be monitored closely, whereas patients with a p.T7FX7 (c.18-21del4bp) mutation have a milder phenotype. Additionally, metabolic alkalosis does not exclude cystinosis, although cystinosis is a cause of proximal renal tubular acidosis.
Collapse
|
17
|
Jaradat S, Al-Rababah B, Hazza I, Akl K, Saca E, Al-Younis D. Molecular analysis of the CTNS gene in Jordanian families with nephropathic cystinosis. Nefrologia 2015; 35:547-53. [DOI: 10.1016/j.nefro.2015.09.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Accepted: 06/10/2015] [Indexed: 10/22/2022] Open
|
18
|
Soliman NA, Elmonem MA, van den Heuvel L, Abdel Hamid RH, Gamal M, Bongaers I, Marie S, Levtchenko E. Mutational Spectrum of the CTNS Gene in Egyptian Patients with Nephropathic Cystinosis. JIMD Rep 2014; 14:87-97. [PMID: 24464559 DOI: 10.1007/8904_2013_288] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2013] [Revised: 12/02/2013] [Accepted: 12/05/2013] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND Nephropathic cystinosis is a rare autosomal recessive disorder caused by mutations in the CTNS gene, encoding for cystinosin, a carrier protein transporting cystine out of lysosomes. Its deficiency leads to cystine accumulation and cell damage in multiple organs, especially in the kidney. In this study, we aimed to provide the first report describing the mutational spectrum of Egyptian patients with nephropathic cystinosis and their genotype-phenotype correlation. METHODS Fifteen Egyptian patients from 13 unrelated families with infantile nephropathic cystinosis were evaluated clinically, biochemically, and genetically. Screening for the common 57-kb deletion was performed by standard multiplex PCR, followed by direct sequencing of the ten coding exons, exon-intron interfaces, and promoter region. RESULTS None of the 15 Egyptian patients had the 57-kb deletion. Twenty-seven mutant alleles and 12 pathogenic mutations were detected including six novel mutations: two frameshift (c.260_261delTT; p.F87SfsX36, c.1032delCinsTG; p.F345CfsX19), one nonsense (c.734G>A; p.W245fsX), two missense (c.1084G>A; pG362R, c.560A>G; p.K187R), and one intronic splicing mutation (IVS3+5g>t). A novel promoter region mutation (1-593-41C>T) seemed to be detected but was excluded as a pathogenic mutation by quantitative real-time PCR analysis. CONCLUSIONS This study could be the basis for future genetic counseling and prenatal diagnosis of patients with nephropathic cystinosis in Egyptian and surrounding populations. The screening for the 57-kb deletion is not recommended anymore outside its geographical distribution, especially in the region of the Middle East. A common Middle Eastern mutation (c.681G>A; E227E) was pointed out and discussed.
Collapse
Affiliation(s)
- Neveen A Soliman
- Department of Pediatrics, Center of Pediatric Nephrology and Transplantation (CPNT), Cairo University, Cairo, Egypt
| | | | | | | | | | | | | | | |
Collapse
|
19
|
Kari JA. Pediatric renal diseases in the Kingdom of Saudi Arabia. World J Pediatr 2012; 8:217-21. [PMID: 22886193 DOI: 10.1007/s12519-012-0360-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 04/03/2012] [Indexed: 12/20/2022]
Abstract
BACKGROUND Pediatric nephrology is a growing subspecialty in the Kingdom of Saudi Arabia (KSA). Pediatric nephrologists are challenged with a different spectrum of renal diseases. Moreover, there is a lack of epidemiological studies for most of these diseases. In this article, we discuss the spectrum of renal diseases in KSA and highlight the differences that exist between reports from KSA and those from other countries. DATA SOURCES PubMed and MEDLINE databases were searched for articles on pediatric renal diseases. RESULTS Genetically mediated renal diseases are considerably high in KSA. Congenital and infantile nephrotic syndrome is higher in KSA than in other countries. Post-infectious glomerular pathology is rather common but is declining, while tropical infections such as schistosomiasis have been controlled. Neurogenic bladder caused by spinal lesion is an important cause of chronic kidney disease among pediatric patients. Renal stones are also more frequent in KSA than in other countries. CONCLUSIONS The spectrum of pediatric renal diseases in KSA is rather different from that reported from Western countries. More epidemiological studies are required to understand the actual incidence and nature of these diseases.
Collapse
Affiliation(s)
- Jameela Abdulaziz Kari
- Department of Pediatrics, Faculty of Medicine, Department of King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia.
| |
Collapse
|
20
|
Khan AO, Aldahmesh MA, Al-Ghadeer H, Mohamed JY, Alkuraya FS. Familial spherophakia with short stature caused by a novel homozygous ADAMTS17 mutation. Ophthalmic Genet 2012; 33:235-9. [PMID: 22486325 DOI: 10.3109/13816810.2012.666708] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Weill-Marchesani syndrome is characterized by spherophakia, short stature, short hands/feet, joint stiffness, and occasional cardiac abnormalities. The phenotype can be caused by recessive ADAMTS10 mutations or heterozygous fibrillin-1 mutation. In contrast, isolated spherophakia with short stature has been associated with three different homozygous ADAMTS17 mutations in three families from Saudi Arabia. The purpose of this report is to determine the genetic cause of isolated spherophakia with short stature in two siblings from a consanguineous Saudi family. METHODS Clinical examination, homozygosity screen, and candidate gene analysis. RESULTS A brother and sister with high myopia were referred for genetic counseling. Ophthalmic examination revealed spherophakia in both and narrow angles in the sister. Axial lengths were not elongated. Although both had short stature, neither had short hands, short feet, joint stiffness, or non-ocular congenital abnormalities. Homozygosity analysis suggested the candidate gene ADAMTS17, which was found to harbor a novel homozygous mutation (p.Asp218ThrfsX41) that segregated with the phenotype. CONCLUSIONS Recessive ADAMTS17 mutations are a recurrent cause of isolated spherophakia with short stature. In Saudi Arabia this phenotype shows allelic heterogeneity rather than founder effect.
Collapse
Affiliation(s)
- Arif O Khan
- Department of Genetics, King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia.
| | | | | | | | | |
Collapse
|
21
|
Genetic basis of cystinosis in Turkish patients: a single-center experience. Pediatr Nephrol 2012; 27:115-21. [PMID: 21786142 PMCID: PMC3501933 DOI: 10.1007/s00467-011-1942-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2010] [Revised: 04/28/2011] [Accepted: 06/01/2011] [Indexed: 10/18/2022]
Abstract
We report the molecular findings for the CTNS gene in 12 Turkish cystinosis patients aged 7-29 years. All presented initially with severe failure to thrive, polyuria, and polydipsia. Cystinosis was diagnosed at age 1 month to 9 years. Seven patients reached end-stage renal failure at ages ranging from 6.5 to 15 years. Whereas three of the remaining five have renal Fanconi syndrome with proteinuria, two have had kidney failure of varying degrees. Molecular analyses involved an initial multiplex polymerase chain reaction (PCR) to determine the presence or absence of the 57-kb northern European founder deletion in CTNS, followed by sequencing of the ten coding exons of CTNS. Comprehensive mutation analysis verified that none of the 12 patients carried the common 57-kb deletion. We identified four previously reported nucleotide variations associated with cystinosis and five new variants: a 10-kb deletion, three missense variants, and a nucleotide substitution in a potential branch point site of intron 4. This study is the first molecular analysis of Turkish cystinosis patients and provides guidance for the molecular diagnosis of cystinosis in this population.
Collapse
|