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Yavas C, Ozgenturk NO, Dogan M, Gezdirici A, Keskin E, İli EG, Dogan T, Celebi E, Bender O, Un C. A Deeper Insight into COL4A3, COL4A4, and COL4A5 Variants and Genotype-Phenotype Correlation of a Turkish Cohort with Alport Syndrome. Mol Syndromol 2024; 15:1-13. [PMID: 38357258 PMCID: PMC10862325 DOI: 10.1159/000533915] [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: 05/16/2023] [Accepted: 08/26/2023] [Indexed: 02/16/2024] Open
Abstract
Introduction Alport syndrome (AS) is an inherited, rare, progressive kidney disease that affects the eye and ear physiology. Pathogenic variants of COL4A5 account for 85% of all cases, while COL4A3 and COL4A4 account for the remaining 15%. Methods Targeted next-generation sequencing of the COL4A3, COL4A4, and COL4A5 genes was performed in 125 Turkish patients with AS. The patients were compared to 45 controls and open-access population data. Results The incidence of AS variants in patients was found as 21.6%. 27 variants were identified as pathogenic/likely pathogenic, 28 as variant of uncertain significance, and 52 as benign/likely benign. We also found 31 novel variants (14 in COL4A3, 6 in COL4A4, and 11 in COL4A5) of which 27 were classified as pathogenic/likely pathogenic. Pathogenic/likely Pathogenic variants were most commonly found in the COL4A5 gene, consistent with the literature. This study contributed novel variants associated with AS to the literature. Conclusion Genetic testing is a crucial part for the diagnosis and management of AS. Studies on the genetic etiology of AS are limited for the Turkish population. We believe that this study will contribute to the literature and the clinical decision-making process of patients with AS and emphasize the importance of genetic counseling.
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Affiliation(s)
- Cuneyd Yavas
- Department of Medical Genetics, Başaksehir Çam and Sakura City Hospital, Istanbul, Turkey
| | - Nehir Ozdemir Ozgenturk
- Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Yildiz Technical University, Istanbul, Turkey
| | - Mustafa Dogan
- Department of Medical Genetics, Başaksehir Çam and Sakura City Hospital, Istanbul, Turkey
| | - Alper Gezdirici
- Department of Medical Genetics, Başaksehir Çam and Sakura City Hospital, Istanbul, Turkey
| | - Ece Keskin
- Haseki Training and Research Hospital, Clinic of Medical Genetic, Istanbul, Turkey
| | - Ezgi Gokpınar İli
- Department of Medical Genetics, Başaksehir Çam and Sakura City Hospital, Istanbul, Turkey
| | - Tunay Dogan
- Department of Pathology, Faculty of Medicine, Istinye University, Istanbul, Turkey
| | - Evrim Celebi
- Department of Medical Genetics, Başaksehir Çam and Sakura City Hospital, Istanbul, Turkey
| | - Onur Bender
- Biotechnology Institute, Ankara University, Ankara, Turkey
| | - Cemal Un
- Department of Biology Molecular Biology Section, Ege University Faculty of Science, İzmir, Turkey
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Gao Y, Yuan L, Yuan J, Yang Y, Wang J, Chen Y, Zhang H, Ai Y, Deng H. Identification of COL4A4 variants in Chinese patients with familial hematuria. Front Genet 2023; 13:1064491. [PMID: 36699462 PMCID: PMC9868811 DOI: 10.3389/fgene.2022.1064491] [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: 10/08/2022] [Accepted: 12/15/2022] [Indexed: 01/11/2023] Open
Abstract
Background: Benign familial hematuria and Alport syndrome are common causes of familial hematuria among children and young adults, which are attributable to variants in the collagen type IV alpha chain genes, COL4A3, COL4A4, or COL4A5. The study was conducted to identify the underlying genetic causes in patients with familial hematuria. Methods: Two unrelated Han-Chinese pedigrees with familial hematuria were recruited for this study. Whole exome sequencing was combined with in silico analysis to identify potential genetic variants, followed by variant confirmation by Sanger sequencing. Reverse transcription, PCR, and Sanger sequencing were performed to evaluate the effect of the detected splicing variant on mRNA splicing. Results: A novel heterozygous splicing c.595-1G>A variant and a known heterozygous c.1715G>C variant in the collagen type IV alpha 4 chain gene (COL4A4) were identified and confirmed in patients of pedigree 1 and pedigree 2, respectively. Complementary DNA analysis indicated this splicing variant could abolish the canonical splice acceptor site and cause a single nucleotide deletion of exon 10, which was predicted to produce a truncated protein. Conclusions: The two COL4A4 variants, c.595-1G>A variant and c.1715G>C (p.Gly572Ala) variant, were identified as the genetic etiologies of two families with familial hematuria, respectively. Our study broadened the variant spectrum of the COL4A4 gene and explained the possible pathogenesis, which will benefit clinical management and genetic counseling.
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Affiliation(s)
- Yanan Gao
- Health Management Center, The Third Xiangya Hospital, Central South University, Changsha, China,Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Lamei Yuan
- Health Management Center, The Third Xiangya Hospital, Central South University, Changsha, China,Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China,Disease Genome Research Center, Central South University, Changsha, China
| | - Jinzhong Yuan
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Yan Yang
- Department of Neurology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Jiangang Wang
- Health Management Center, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Yong Chen
- National Health Committee Key Laboratory of Birth Defects for Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, China
| | - Hao Zhang
- Department of Nephrology, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Yinze Ai
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China
| | - Hao Deng
- Health Management Center, The Third Xiangya Hospital, Central South University, Changsha, China,Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, China,Disease Genome Research Center, Central South University, Changsha, China,*Correspondence: Hao Deng,
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Claus LR, Snoek R, Knoers NVAM, van Eerde AM. Review of genetic testing in kidney disease patients: Diagnostic yield of single nucleotide variants and copy number variations evaluated across and within kidney phenotype groups. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2022; 190:358-376. [PMID: 36161467 PMCID: PMC9828643 DOI: 10.1002/ajmg.c.31995] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 07/02/2022] [Accepted: 08/18/2022] [Indexed: 01/29/2023]
Abstract
Genetic kidney disease comprises a diverse group of disorders. These can roughly be divided in the phenotype groups congenital anomalies of the kidney and urinary tract, ciliopathies, glomerulopathies, stone disorders, tubulointerstitial kidney disease, and tubulopathies. Many etiologies can lead to chronic kidney disease that can progress to end-stage kidney disease. Despite each individual disease being rare, together these genetic disorders account for a large proportion of kidney disease cases. With the introduction of massively parallel sequencing, genetic testing has become more accessible, but a comprehensive analysis of the diagnostic yield is lacking. This review gives an overview of the diagnostic yield of genetic testing across and within the full range of kidney disease phenotypes through a systematic literature search that resulted in 115 included articles. Patient, test, and cohort characteristics that can influence the diagnostic yield are highlighted. Detection of copy number variations and their contribution to the diagnostic yield is described for all phenotype groups. Also, the impact of a genetic diagnosis for a patient and family members, which can be diagnostic, therapeutic, and prognostic, is shown through the included articles. This review will allow clinicians to estimate an a priori probability of finding a genetic cause for the kidney disease in their patients.
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Affiliation(s)
- Laura R. Claus
- Department of GeneticsUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Rozemarijn Snoek
- Department of GeneticsUniversity Medical Center UtrechtUtrechtThe Netherlands
| | - Nine V. A. M. Knoers
- Department of GeneticsUniversity Medical Center GroningenGroningenThe Netherlands
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Kim SY, Kim BJ, Oh DY, Han JH, Yi N, Kim NJ, Park MK, Keum C, Seo GH, Choi BY. Improving genetic diagnosis by disease-specific, ACMG/AMP variant interpretation guidelines for hearing loss. Sci Rep 2022; 12:12457. [PMID: 35864128 PMCID: PMC9304357 DOI: 10.1038/s41598-022-16661-x] [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: 08/04/2021] [Accepted: 07/13/2022] [Indexed: 12/29/2022] Open
Abstract
The 2018 Hearing Loss Expert Panel (HL-EP)-specific guidelines specified from the universal 2015 ACMG/AMP guidelines are proposed to be used in genetic HL, which prompted this study. A genetic HL cohort comprising 135 unrelated probands with available exome sequencing data was established. Overall, 169 variants were prioritized as candidates and interpreted using the 2015 ACMG/AMP and 2018 HL-EP guidelines. Changes in rule application and variant classification between the guidelines were compared. The concordance rate of variant classification of each variant between the guidelines was 71.60%, with significant difference. The proportion of pathogenic variants increased from 13.02% (2015) to 29.59% (2018). Variant classifications of autosomal recessive (AR) variants that previously belonged to VUS or likely pathogenic in the 2015 guidelines were changed toward pathogenic in the 2018 guidelines more frequently than those of autosomal dominant variants (29.17% vs. 6.38%, P = 0.005). Stratification of the PM3 and PP1 rules in the 2018 guidelines led to more substantial escalation than that in the 2015 guidelines. We compared the disease-specific guidelines (2018) with the universal guidelines (2015) using real-world data. Owing to the sophistication of case-level data, the HL-specific guidelines have more explicitly classified AR variants toward "likely pathogenic" or "pathogenic", serving as potential references for other recessive genetic diseases.
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Affiliation(s)
- So Young Kim
- grid.410886.30000 0004 0647 3511Department of Otorhinolaryngology-Head and Neck Surgery, CHA Bundang Medical Center, CHA University, Seongnam, South Korea
| | - Bong Jik Kim
- grid.254230.20000 0001 0722 6377Department of Otolaryngology-Head and Neck Surgery, Chungnam National University Sejong Hospital, Chungnam National University College of Medicine, Daejeon, South Korea
| | - Doo Yi Oh
- grid.412480.b0000 0004 0647 3378Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Jin Hee Han
- grid.412480.b0000 0004 0647 3378Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Nayoung Yi
- grid.254230.20000 0001 0722 6377Department of Otolaryngology-Head and Neck Surgery, Chungnam National University Sejong Hospital, Chungnam National University College of Medicine, Daejeon, South Korea ,grid.412480.b0000 0004 0647 3378Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
| | - Namju Justin Kim
- grid.412480.b0000 0004 0647 3378Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea ,grid.152326.10000 0001 2264 7217Department of Biological Sciences, Vanderbilt University, Nashville, USA
| | - Moo Kyun Park
- grid.31501.360000 0004 0470 5905Department of Otorhinolaryngology, Seoul National University College of Medicine, Seoul, South Korea
| | | | | | - Byung Yoon Choi
- grid.412480.b0000 0004 0647 3378Department of Otorhinolaryngology-Head and Neck Surgery, Seoul National University Bundang Hospital, Seongnam, South Korea
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Cocorpus J, Hager MM, Benchimol C, Bijol V, Salem F, Punj S, Castellanos L, Singer P, Sethna CB, Basalely A. COL4A4 variant recently identified: lessons learned in variant interpretation-a case report. BMC Nephrol 2022; 23:253. [PMID: 35842573 PMCID: PMC9287857 DOI: 10.1186/s12882-022-02866-9] [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: 06/28/2022] [Indexed: 11/10/2022] Open
Abstract
Background Alport syndrome is a hereditary kidney disease characterized by hematuria and proteinuria. Although there have been reports of autosomal dominant COL4A4 variants, this is likely an underdiagnosed condition. Improved access to affordable genetic testing has increased the diagnosis of Alport syndrome. As genetic testing becomes ubiquitous, it is imperative that clinical nephrologists understand the benefits and challenges associated with clinical genetic testing. Case Presentation We present a family of Mexican descent with a heterozygous COL4A4 variant (c.5007delC, ClinVar accession numbers: SCV001580980.2, SCV001993731.1) not previously discussed in detail in the literature. The proband received a biopsy diagnosis suggestive of Fabry disease 18 years after she first developed hematuria and progressed to chronic kidney disease stage III. One year later, the proband was provisionally diagnosed with Alport syndrome after a variant of uncertain significance in the COL4A4 gene was identified following targeted family variant testing of her daughter. Upon review of the medical histories of the proband’s children and niece, all but one had the same variant. Of the four with the variant, three display clinical symptoms of hematuria, and/or proteinuria. The youngest of the four, only months old, has yet to exhibit clinical symptoms. Despite these findings there was a considerable delay in synthesizing this data, as patients were tested in different commercial genetic testing laboratories. Subsequently, understanding this family’s inheritance pattern, family history, and clinical symptoms, as well as the location of the COL4A4 variant resulted in the upgrade of the variant’s classification. Although the classification of this variant varied among different clinical genetic testing laboratories, the consensus was that this variant is likely pathogenic. Conclusions This COL4A4 variant (c.5007delC) not yet discussed in detail in the literature is associated with Alport syndrome. The inheritance pattern is suggestive of autosomal dominant inheritance. This report highlights the intricacies of variant interpretation and classification, the siloed nature of commercial genetic testing laboratories, and the importance of a thorough family history for proper variant interpretation. Additionally, the cases demonstrate the varied clinical presentations of Alport syndrome and suggest the utility of early screening, diagnosis, monitoring, and treatment.
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Affiliation(s)
- Jenelle Cocorpus
- Pediatric Nephrology, Cohen Children's Medical Center of New York, 269-01 76th Avenue, New Hyde Park, NY, 11040, USA
| | | | | | - Vanesa Bijol
- Renal Pathology, Northwell Health, Lake Success, NY, USA
| | - Fadi Salem
- Pathology, Molecular and Cell Based Medicine, Mount Sinai, New York, NY, USA
| | | | - Laura Castellanos
- Pediatric Nephrology, Cohen Children's Medical Center of New York, 269-01 76th Avenue, New Hyde Park, NY, 11040, USA
| | - Pamela Singer
- Pediatric Nephrology, Cohen Children's Medical Center of New York, 269-01 76th Avenue, New Hyde Park, NY, 11040, USA
| | - Christine B Sethna
- Pediatric Nephrology, Cohen Children's Medical Center of New York, 269-01 76th Avenue, New Hyde Park, NY, 11040, USA
| | - Abby Basalely
- Pediatric Nephrology, Cohen Children's Medical Center of New York, 269-01 76th Avenue, New Hyde Park, NY, 11040, USA.
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Liang Y, Lv Z, Huang G, Qin J, Li H, Nong F, Wen B. Prognostic significance of abnormal matrix collagen remodeling in colorectal cancer based on histologic and bioinformatics analysis. Oncol Rep 2020; 44:1671-1685. [PMID: 32945508 PMCID: PMC7448414 DOI: 10.3892/or.2020.7729] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 07/20/2020] [Indexed: 02/06/2023] Open
Abstract
As the major component of the tumor matrix, collagen greatly influences tumor invasion and prognosis. The present study compared the remodeling of collagen and collagenase in 56 patients with colorectal cancer (CRC) using Sirius red stain and immunohistochemistry, exploring the relationship between collagen remodeling and the prognosis of CRC. Weak or strong changes in collagen fiber arrangement in birefringence were observed. With the exception of a higher density, weak changes equated to a similar arrangement in normal collagen, while strong changes facilitated cross-linking into bundles. Compared with normal tissues, collagen I (COL I) and III (COL III) deposition was significantly increased in CRC tissues, and was positively correlated with the metastasis status. In tissues without distant metastasis, collagen IV (COL IV) levels were higher than that in normal tissues, while in tissues with distant metastasis, collagen IV expression was significantly lower. Furthermore, the expression of matrix metalloproteinase (MMP)-1, MMP-2, MMP-7, MMP-9 and lysyl oxidase-like 2 (LOXL2) was found to be elevated in the cancer stroma, which contributed to the hyperactive remodeling of collagen. The association between collagen-related genes and the occurrence and prognosis of CRC were analyzed using biometric databases. The results indicated that patients with upregulated expression of a combination of coding genes for collagen and collagenase exhibited poorer overall survival times. The coding genes COL1A1-2, COL3A1, COL4A3, COL4A6 and MMP2 may therefore be used as biomarkers to predict the prognosis of patients with CRC. Furthermore, the results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis suggest that collagen may promote tumor development by activating platelets. Collectively, the abnormal collagen remodeling, including associated protein and coding genes is associated with the tumorigenesis and metastasis, affecting the prognosis of patients with CRC.
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Affiliation(s)
- Yuqi Liang
- Department of Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510000, P.R. China
| | - Zhihao Lv
- Department of Anorectal Surgery, Zhongshan Hospital Affiliated to Guangzhou University of Chinese Medicine, Zhongshan, Guangdong 528400, P.R. China
| | - Guohang Huang
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong, SAR 999077, P.R. China
| | - Jingchun Qin
- Department of Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510000, P.R. China
| | - Huixuan Li
- Department of Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510000, P.R. China
| | - Feifei Nong
- Department of Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510000, P.R. China
| | - Bin Wen
- Department of Science and Technology Innovation Center, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong 510000, P.R. China
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How to resolve confusion in the clinical setting for the diagnosis of heterozygous COL4A3 or COL4A4 gene variants? Discussion and suggestions from nephrologists. Clin Exp Nephrol 2020; 24:651-656. [PMID: 32232700 PMCID: PMC7371658 DOI: 10.1007/s10157-020-01880-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Accepted: 03/17/2020] [Indexed: 12/22/2022]
Abstract
Both thin basement membrane nephropathy (TBMN) and autosomal dominant Alport syndrome (ADAS) are types of hereditary nephritis resulting from heterozygous mutations in COL4A3 or COL4A4 genes. Although TBMN is characterized by hematuria and thinning of the glomerular basement membrane (GBM) with excellent renal prognosis, some patients develop end-stage renal disease (ESRD) later in life. In contrast, although AS is characterized by progressive nephropathy with lamellation of the GBM, there are some patients diagnosed with ADAS from a family history of ESRD but who only suffer from hematuria with GBM thinning. These findings indicate a limitation in distinction between TBMN and ADAS. Diagnosis of AS is significant because it facilitates careful follow-up and early treatment, whereas diagnosis of TBMN can underestimate the risk of ESRD. However, some experts are against using the term ADAS as the phenotypes of heterozygous variants vary from no urinary abnormality to ESRD, even between family members with the same mutations, indicating that unknown secondary factors may play a large role in the disease severity. These diagnostic difficulties result in significant confusion in clinical settings. Moreover, recent studies revealed that the number of patients with chronic kidney disease caused by these gene mutations is far higher than previously thought. The aim of this article is to review differing opinions regarding the diagnosis of heterozygous COL4A3 or COL4A4 variants, and to highlight the importance for nephrologists to recognize this disease, and the importance of the need to reclassify this disease to minimize the current confusion.
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8
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Schapiro D, Daga A, Lawson JA, Majmundar AJ, Lovric S, Tan W, Warejko JK, Fessi I, Rao J, Airik M, Gee HY, Schneider R, Widmeier E, Hermle T, Ashraf S, Jobst-Schwan T, van der Ven AT, Nakayama M, Shril S, Braun DA, Hildebrandt F. Panel sequencing distinguishes monogenic forms of nephritis from nephrosis in children. Nephrol Dial Transplant 2019; 34:474-485. [PMID: 30295827 DOI: 10.1093/ndt/gfy050] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Accepted: 01/21/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Alport syndrome (AS) and atypical hemolytic-uremic syndrome (aHUS) are rare forms of chronic kidney disease (CKD) that can lead to a severe decline of renal function. Steroid-resistant nephrotic syndrome (SRNS) is more common than AS and aHUS and causes 10% of childhood-onset CKD. In recent years, multiple monogenic causes of AS, aHUS and SRNS have been identified, but their relative prevalence has yet to be studied together in a typical pediatric cohort of children with proteinuria and hematuria. We hypothesized that identification of causative mutations by whole exome sequencing (WES) in known monogenic nephritis and nephrosis genes would allow distinguishing nephritis from nephrosis in a typical pediatric group of patients with both proteinuria and hematuria at any level. METHODS We therefore conducted an exon sequencing (WES) analysis for 11 AS, aHUS and thrombotic thrombocytopenic purpura-causing genes in an international cohort of 371 patients from 362 families presenting with both proteinuria and hematuria before age 25 years. In parallel, we conducted either WES or high-throughput exon sequencing for 23 SRNS-causing genes in all patients. RESULTS We detected pathogenic mutations in 18 of the 34 genes analyzed, leading to a molecular diagnosis in 14.1% of families (51 of 362). Disease-causing mutations were detected in 3 AS-causing genes (4.7%), 3 aHUS-causing genes (1.4%) and 12 NS-causing genes (8.0%). We observed a much higher mutation detection rate for monogenic forms of CKD in consanguineous families (35.7% versus 10.1%). CONCLUSIONS We present the first estimate of relative frequency of inherited AS, aHUS and NS in a typical pediatric cohort with proteinuria and hematuria. Important therapeutic and preventative measures may result from mutational analysis in individuals with proteinuria and hematuria.
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Affiliation(s)
- David Schapiro
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ankana Daga
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jennifer A Lawson
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Amar J Majmundar
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Svjetlana Lovric
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Weizhen Tan
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jillian K Warejko
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Inés Fessi
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Jia Rao
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Merlin Airik
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Heon Yung Gee
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Ronen Schneider
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Eugen Widmeier
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Tobias Hermle
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Shazia Ashraf
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Tilman Jobst-Schwan
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Amelie T van der Ven
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Makiko Nakayama
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Shirlee Shril
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Daniela A Braun
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Friedhelm Hildebrandt
- Department of Medicine, Division of Nephrology, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
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9
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Yamamura T, Nozu K, Minamikawa S, Horinouchi T, Sakakibara N, Nagano C, Aoto Y, Ishiko S, Nakanishi K, Shima Y, Nagase H, Rossanti R, Ye MJ, Nozu Y, Ishimori S, Morisada N, Kaito H, Iijima K. Comparison between conventional and comprehensive sequencing approaches for genetic diagnosis of Alport syndrome. Mol Genet Genomic Med 2019; 7:e883. [PMID: 31364286 PMCID: PMC6732293 DOI: 10.1002/mgg3.883] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 06/05/2019] [Accepted: 07/05/2019] [Indexed: 12/19/2022] Open
Abstract
Background Alport syndrome (AS) is a hereditary disease caused by mutations in COL4A3‐5 genes. Recently, comprehensive genetic analysis has become the first‐line diagnostic tool for AS. However, no reports comparing mutation identification rates between conventional sequencing and comprehensive screening have been published. Methods In this study, 441 patients clinically suspected of having AS were divided into two groups and compared. The initial mutational analysis method involved targeted exome sequencing using next‐generation sequencing (NGS) (n = 147, NGS group) or Sanger sequencing for COL4A3/COL4A4/COL4A5 (n = 294, Sanger group). Results In the NGS group, 126 patients (86%) were diagnosed with AS by NGS, while two had pathogenic mutations in other genes, NPHS1 and EYA1. Further, 239 patients (81%) were diagnosed with AS by initial analysis in the Sanger group. Thirteen patients who were negative for mutation detection in the Sanger group were analyzed by NGS; three were diagnosed with AS. Two had mutations in CLCN5 or LAMB2. The final variant detection rate was 90%. Discussion Our results reveal that Sanger sequencing and targeted exome sequencing have high diagnostic ability. NGS also has the advantage of detecting other inherited kidney diseases and pathogenic mutations missed by Sanger sequencing.
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Affiliation(s)
- Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Shogo Minamikawa
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Tomoko Horinouchi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Nana Sakakibara
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Yuya Aoto
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Shinya Ishiko
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Koichi Nakanishi
- Department of Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, Nishihara, Okinawa, Japan
| | - Yuko Shima
- Department of Pediatrics, Wakayama Medical University, Wakayama, Japan
| | - Hiroaki Nagase
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Rini Rossanti
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Ming J Ye
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Yoshimi Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Shingo Ishimori
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Naoya Morisada
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Hiroshi Kaito
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Hyogo, Japan
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10
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Features of Autosomal Recessive Alport Syndrome: A Systematic Review. J Clin Med 2019; 8:jcm8020178. [PMID: 30717457 PMCID: PMC6406612 DOI: 10.3390/jcm8020178] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 01/27/2019] [Accepted: 01/31/2019] [Indexed: 01/16/2023] Open
Abstract
Alport syndrome (AS) is one of the most frequent hereditary nephritis leading to end-stage renal disease (ESRD). Although X-linked (XLAS) inheritance is the most common form, cases with autosomal recessive inheritance with mutations in COL4A3 or COL4A4 are being increasingly recognized. A systematic review was conducted on autosomal recessive Alport syndrome (ARAS). Electronic databases were searched using related terms (until Oct 10th, 2018). From 1601 articles searched, there were 26 eligible studies with 148 patients. Female and male patients were equally affected. About 62% of patients had ESRD, 64% had sensorineural hearing loss (SNHL) and 17% had ocular manifestation. The median at onset was 2.5 years for hematuria (HU), 21 years for ESRD, and 13 years for SNHL. Patients without missense mutations had more severe outcomes at earlier ages, while those who had one or two missense mutations had delayed onset and lower prevalence of extrarenal manifestations. Of 49 patients with kidney biopsy available for electron microscopy (EM) pathology, 42 (86%) had typical glomerular basement membrane (GBM) changes, while 5 (10%) patients showed GBM thinning only. SNHL developed earlier than previously reported. There was a genotype phenotype correlation according to the number of missense mutations. Patients with missense mutations had delayed onset of hematuria, ESRD, and SNHL and lower prevalence of extrarenal manifestations.
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11
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Mutation analysis of COL4A3 and COL4A4 genes in a Chinese autosomal-dominant Alport syndrome family. J Genet 2018; 96:389-392. [PMID: 28674241 DOI: 10.1007/s12041-017-0786-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Autosomal dominant Alport syndrome (ADAS) accounts for 5% of all cases of Alport syndrome (AS), a primary basement membrane disorder arising from mutations in genes encoding the type IV collagen protein family.Mutations in COL4A3 and COL4A4 genes were reported to be associated with ADAS. In this study, clinical data in a large consanguineous family with seven affected members were reviewed, and genomic DNA was extracted. For mutation screening, all exons of COL4A3 and COL4A4 genes were polymerase chain reaction-amplified and direct sequenced from genomic DNA, and the mutations were analyzed by comparing with members in this family, 100 ethnicitymatched controls and the sequence of COL4A3 and COL4A4 genes from GenBank. A novel mutation determining a nucleotide change was found, i.e. c.4195 A>T (p.Met1399Leu) at 44th exon of COL4A4 gene, and this mutation showed heterozygous in all patients of this family. Also a novel intron mutation (c.4127+11 C>T) was observed at COL4A4 gene. Thus the novel missense mutation c.4195 A>T (p.Met1399Leu) and the intron mutation (c.4127+11 C>T) at COL4A4 gene might be responsible for ADAS of this family. Our results broadened the spectrum of mutations in COL4A4 and had important implications in the diagnosis, prognosis, and genetic counselling of ADAS.
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12
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Papazachariou L, Papagregoriou G, Hadjipanagi D, Demosthenous P, Voskarides K, Koutsofti C, Stylianou K, Ioannou P, Xydakis D, Tzanakis I, Papadaki A, Kallivretakis N, Nikolakakis N, Perysinaki G, Gale DP, Diamantopoulos A, Goudas P, Goumenos D, Soloukides A, Boletis I, Melexopoulou C, Georgaki E, Frysira E, Komianou F, Grekas D, Paliouras C, Alivanis P, Vergoulas G, Pierides A, Daphnis E, Deltas C. Frequent COL4 mutations in familial microhematuria accompanied by later-onset Alport nephropathy due to focal segmental glomerulosclerosis. Clin Genet 2017. [PMID: 28632965 DOI: 10.1111/cge.13077] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Familial microscopic hematuria (FMH) is associated with a genetically heterogeneous group of conditions including the collagen-IV nephropathies, the heritable C3/CFHR5 nephropathy and the glomerulopathy with fibronectin deposits. The clinical course varies widely, ranging from isolated benign familial hematuria to end-stage renal disease (ESRD) later in life. We investigated 24 families using next generation sequencing (NGS) for 5 genes: COL4A3, COL4A4, COL4A5, CFHR5 and FN1. In 17 families (71%), we found 15 pathogenic mutations in COL4A3/A4/A5, 9 of them novel. In 5 families patients inherited classical AS with hemizygous X-linked COL4A5 mutations. Even more patients developed later-onset Alport-related nephropathy having inherited heterozygous COL4A3/A4 mutations that cause thin basement membranes. Amongst 62 heterozygous or hemizygous patients, 8 (13%) reached ESRD, while 25% of patients with heterozygous COL4A3/A4 mutations, aged >50-years, reached ESRD. In conclusion, COL4A mutations comprise a frequent cause of FMH. Heterozygous COL4A3/A4 mutations predispose to renal function impairment, supporting that thin basement membrane nephropathy is not always benign. The molecular diagnosis is essential for differentiating the X-linked from the autosomal recessive and dominant inheritance. Finally, NGS technology is established as the gold standard for the diagnosis of FMH and associated collagen-IV glomerulopathies, frequently averting the need for invasive renal biopsies.
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Affiliation(s)
- L Papazachariou
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - G Papagregoriou
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - D Hadjipanagi
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - P Demosthenous
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - K Voskarides
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - C Koutsofti
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - K Stylianou
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - P Ioannou
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - D Xydakis
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - I Tzanakis
- Department of Nephrology, General Hospital of Chania, Crete, Greece
| | - A Papadaki
- Department of Nephrology, General Hospital of Chania, Crete, Greece
| | - N Kallivretakis
- Department of Nephrology, General Hospital of Chania, Crete, Greece
| | - N Nikolakakis
- Division of Nephrology, General Hospital of Rethymno, Crete, Greece
| | - G Perysinaki
- Division of Nephrology, General Hospital of Rethymno, Crete, Greece
| | - D P Gale
- UCL Division of Medicine and Centre for Nephrology, University College London, London, UK
| | | | - P Goudas
- IATOS Dialysis Unit, Patra, Greece
| | - D Goumenos
- Department of Nephrology, Medical School, University of Patras, Patra, Greece
| | - A Soloukides
- Protypo Nefrologiko Athinon Dialysis Center, Athens, Greece
| | - I Boletis
- Department of Nephrology, Laikon Hospital, Athens, Greece
| | - C Melexopoulou
- Department of Nephrology, Laikon Hospital, Athens, Greece
| | - E Georgaki
- Pediatric Nephrology Unit, "IASO" Children's Hospital, Athens, Greece
| | - E Frysira
- Department of Pediatrics, Athens University Medical School, Agia Sophia Children's Hospital, Athens, Greece
| | - F Komianou
- Department of Medical Genetics, Athens University Medical School, Agia Sophia Children's Hospital, Athens, Greece
| | - D Grekas
- University Hospital AXEPA, Thessaloniki, Greece
| | - C Paliouras
- Department of Nephrology, General Hospital of Rhodes, Rhodes, Greece
| | - P Alivanis
- Department of Nephrology, General Hospital of Rhodes, Rhodes, Greece
| | - G Vergoulas
- Organ Transplant Unit, Hippokratio General Hospital, Thessaloniki, Greece
| | - A Pierides
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus.,Department of Nephrology, Hippocrateon Hospital, Nicosia, Cyprus
| | - E Daphnis
- Department of Nephrology, University of Crete-Greece, Heraklion, Greece
| | - C Deltas
- Molecular Medicine Research Center & Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
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13
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Gillion V, Jadoul M, Aydin S, Godefroid N. ANCA vasculitis in a patient with Alport syndrome: a difficult diagnosis but a treatable disease! BMC Nephrol 2017; 18:105. [PMID: 28356090 PMCID: PMC5372285 DOI: 10.1186/s12882-017-0527-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 03/23/2017] [Indexed: 11/10/2022] Open
Abstract
Background Alport syndrome and ANCA-associated vasculitis are both rare diseases. The co-existence of these two conditions has never been reported. There is no obvious pathogenic link between these two glomerular diseases. The management of this case highlights the importance of a systematic approach when investigating the unexpected unfavourable evolution of a known glomerulopathy. Case presentation A-17 year old caucasian boy with a genetically proven X-linked Alport syndrome presented with progressive dyspnea, fatigue and pallor. His blood tests showed a severe anemia (Hb 6.9 g/dl) with acute worsening of kidney function (serum creatinine, normal 9 months earlier, was now 3.6 mg/dl). Microscopic hematuria and proteinuria also worsened. He soon developed signs of alveolar hemorrhage. Serological tests showed the presence of perinuclear ANCA with anti MPO specificity. Kidney biopsy showed a necrotizing and crescentic glomerulonephritis. Pulses of methylprednisolone were given in combination with plasmapheresis. The patient further received 6 pulses of cyclophosphamide, followed by maintenance oral azathioprine. During the 15-months follow up he remained well with serum creatinine back to normal, and some residual proteinuria and hematuria ascribed to Alport syndrome. Conclusion We report a young patient with the coexistence of Alport syndrome and ANCA associated vasculitis. Clinicians should be aware of the possibility of a second acquired disease in a patient with a known kidney disease, genetic in this case. This coexistence is very rare, but should be considered even if both diseases are rare, if the evolution is atypical for the single (known) primary disease. The diagnosis of the added vasculitis prompted in our case the initiation of immunosuppressive drugs, with a favourable outcome.
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Affiliation(s)
- Valentine Gillion
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Michel Jadoul
- Division of Nephrology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium.
| | - Selda Aydin
- Division of Pathology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
| | - Nathalie Godefroid
- Division of Pediatric Nephrology, Cliniques Universitaires Saint-Luc, Université Catholique de Louvain, Brussels, Belgium
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14
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Savva I, Pierides A, Deltas C. RAAS inhibition and the course of Alport syndrome. Pharmacol Res 2016; 107:205-210. [PMID: 26995302 DOI: 10.1016/j.phrs.2016.03.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 03/04/2016] [Accepted: 03/14/2016] [Indexed: 12/26/2022]
Abstract
Alport syndrome (AS) is a hereditary progressive glomerulonephritis with a high life-time risk for end-stage renal disease (ESRD). Most patients will reach ESRD before the age of 30 years, while a subset of them with milder mutations will do so at older ages, even after 50 years. Frequent extrarenal manifestations are hearing loss and ocular abnormalities. AS is a genetically heterogeneous collagen IV nephropathy, with 85% of the cases caused by mutations in the X-linked COL4A5 gene and the rest by homozygous or compound heterozygous mutations in either the COL4A3 or the COL4A4 gene on chromosome 2q36-37. There is no radical cure for the disease and attempts to use various stem cell therapies in animal models have been met with ambiguous success. However, effective treatment has been accomplished with pharmacological intervention at the renin-angiotensin-aldosterone system (RAAS), first in animal models of AS and more recently in humans. Angiotensin converting enzyme inhibitors (ACEis) and angiotensin receptor blockers (ARBs) have been shown to significantly delay the progression of chronic kidney disease and the onset of ESRD. Also, renin inhibitors and aldosterone blockade were used with positive results, while the combination of ACEis and ARBs was met with mixed success. An important study, the EARLY-PROTECT, aims at evaluating the efficacy of ACEis when administered very early on in children with AS. Novel therapies are also tested experimentally or are under design in animal models by several groups, including the use of amniotic fluid stem cells and synthetic chaperones.
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Affiliation(s)
- Isavella Savva
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus
| | - Alkis Pierides
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus; Department of Nephrology, Hippocrateon Hospital, Nicosia, Cyprus
| | - Constantinos Deltas
- Molecular Medicine Research Center and Laboratory of Molecular and Medical Genetics, Department of Biological Sciences, University of Cyprus, Cyprus.
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15
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Nabais Sá MJ, Sampaio S, Oliveira A, Alves S, Moura CP, Silva SE, Castro R, Araújo JA, Rodrigues M, Neves F, Seabra J, Soares C, Gaspar MA, Tavares I, Freitas L, Sousa TC, Henriques AC, Costa FT, Morgado E, Sousa FT, Sousa JP, da Costa AG, Filipe R, Garrido J, Montalban J, Ponce P, Alves R, Faria B, Carvalho MF, Pestana M, Carvalho F, Oliveira JP. Collagen type IV-related nephropathies in Portugal: pathogenic COL4A5 mutations and clinical characterization of 22 families. Clin Genet 2014; 88:462-7. [PMID: 25307721 DOI: 10.1111/cge.12522] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 10/08/2014] [Accepted: 10/08/2014] [Indexed: 11/28/2022]
Abstract
Alport syndrome (AS) is caused by pathogenic mutations in the genes encoding α3, α4 or α5 chains of collagen IV (COL4A3/COL4A4/COL4A5), resulting in hematuria, chronic renal failure (CRF), sensorineural hearing loss (SNHL) and ocular abnormalities. Mutations in the X-linked COL4A5 gene have been identified in 85% of the families (XLAS). In this study, 22 of 60 probands (37%) of unrelated Portuguese families, with clinical diagnosis of AS and no evidence of autosomal inheritance, had pathogenic COL4A5 mutations detected by Sanger sequencing and/or multiplex-ligation probe amplification, of which 12 (57%) are novel. Males had more severe and earlier renal and extrarenal complications, but microscopic hematuria was a constant finding irrespective of gender. Nonsense and splice site mutations, as well as small and large deletions, were associated with younger age of onset of SNHL in males, and with higher risk of CRF and SNHL in females. Pathogenic COL4A3 or COL4A4 mutations were subsequently identified in more than half of the families without a pathogenic mutation in COL4A5. The lower than expected prevalence of XLAS in Portuguese families warrants the use of next-generation sequencing for simultaneous COL4A3/COL4A4/COL4A5 analysis, as first-tier approach to the genetic diagnosis of collagen type IV-related nephropathies.
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Affiliation(s)
- M J Nabais Sá
- Department of Genetics, Faculty of Medicine, Porto, Portugal.,Unit of Research and Development of Nephrology (FCT-725), Faculty of Medicine, University of Porto, Porto, Portugal
| | - S Sampaio
- Unit of Research and Development of Nephrology (FCT-725), Faculty of Medicine, University of Porto, Porto, Portugal.,Department of Nephrology, Porto, Portugal
| | - A Oliveira
- Department of Nephrology, Porto, Portugal
| | - S Alves
- Department of Genetics, Faculty of Medicine, Porto, Portugal
| | - C P Moura
- Department of Otolaryngology, Porto, Portugal.,Medical Genetics Outpatient Clinic, Porto, Portugal
| | - S E Silva
- Department of Ophthalmology, Hospital de São João, Porto, Portugal
| | - R Castro
- Department of Nephrology, Centro Hospitalar de Trás-os-Montes e Alto Douro, Vila Real, Portugal
| | - J A Araújo
- Department of Nephrology, Hospital dos Marmeleiros, Funchal, Portugal
| | - M Rodrigues
- Department of Medical Genetics, Hospital Dona Estefânia, Lisboa, Portugal
| | - F Neves
- Dialysis Clinic of Santarém, NephroCare-Portugal, Santarém, Portugal
| | - J Seabra
- Department of Nephrology, Centro Hospitalar Vila Nova de Gaia/Espinho, Vila Nova de Gaia, Portugal
| | - C Soares
- Department of Nephrology, Hospital de Braga, Braga, Portugal
| | - M A Gaspar
- Dialysis Clinic of Restelo, NephroCare-Portugal, Lisboa, Portugal
| | - I Tavares
- Unit of Research and Development of Nephrology (FCT-725), Faculty of Medicine, University of Porto, Porto, Portugal.,Dialysis Clinic of Santo Tirso, Uninefro, Santo Tirso, Portugal
| | - L Freitas
- Department of Nephrology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal
| | - T C Sousa
- Department of Nephrology, Hospital de São Teotónio, Viseu, Portugal.,Dialysis Clinic of Guarda, NephroCare-Portugal, Guarda, Portugal
| | - A C Henriques
- Dialysis Clinic of Braga, NephroCare-Portugal, Braga, Portugal
| | - F T Costa
- Department of Nephrology, Hospital Garcia de Orta, Almada, Portugal
| | - E Morgado
- Department of Nephrology, Hospital de Faro, Faro, Portugal
| | - F T Sousa
- Dialysis Clinic of Montijo, NephroCare-Portugal, Montijo, Portugal
| | - J P Sousa
- Department of Nephrology, Centro Hospitalar e Universitário de Coimbra, Coimbra, Portugal.,Dialysis Clinic of Coimbra, NephroCare-Portugal, Coimbra, Portugal
| | - A G da Costa
- Department of Nephrology, Hospital de Santa Maria, Lisboa, Portugal
| | - R Filipe
- Department of Nephrology, Hospital Amato Lusitano, Castelo Branco, Portugal
| | - J Garrido
- Department of Nephrology, Hospital de São Teotónio, Viseu, Portugal
| | - J Montalban
- Dialysis Clinic of Covilhã, NephroCare-Portugal, Covilhã, Portugal
| | - P Ponce
- Dialysis Clinic of Lumiar, NephroCare-Portugal, Lisboa, Portugal
| | - R Alves
- Dialysis Clinic of Viseu, NephroCare-Portugal, Viseu, Portugal
| | - B Faria
- Dialysis Clinic of Guarda, NephroCare-Portugal, Guarda, Portugal
| | - M F Carvalho
- Unit of Renal Morphology, Department of Nephrology, Hospital Curry Cabral, Lisboa, Portugal
| | - M Pestana
- Unit of Research and Development of Nephrology (FCT-725), Faculty of Medicine, University of Porto, Porto, Portugal.,Department of Nephrology, Porto, Portugal
| | - F Carvalho
- Department of Genetics, Faculty of Medicine, Porto, Portugal
| | - J P Oliveira
- Department of Genetics, Faculty of Medicine, Porto, Portugal.,Unit of Research and Development of Nephrology (FCT-725), Faculty of Medicine, University of Porto, Porto, Portugal.,Medical Genetics Outpatient Clinic, Porto, Portugal
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