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Ullah M, Rehman AU, Folcher M, Ullah A, Usman F, Rashid A, Khan B, Quinodoz M, Ansar M, Rivolta C. A Novel Intronic Deletion in PDE6B Causes Autosomal Recessive Retinitis Pigmentosa by Interfering with RNA Splicing. Ophthalmic Res 2023; 66:878-884. [PMID: 37094557 DOI: 10.1159/000530800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Accepted: 04/17/2023] [Indexed: 04/26/2023]
Abstract
INTRODUCTION Retinitis pigmentosa (RP) is a rare degenerative retinal disease caused by mutations in approximately seventy genes. Currently, despite the availability of large-scale DNA sequencing technologies, ∼30-40% of patients still cannot be diagnosed at the molecular level. In this study, we investigated a novel intronic deletion of PDE6B, encoding the beta subunit of phosphodiesterase 6 in association with recessive RP. METHODS Three unrelated consanguineous families were recruited from the northwestern part of Pakistan. Whole exome sequencing was performed for the proband of each family, and the data were analyzed according to an in-house computer pipeline. Relevant DNA variants in all available members of these families were assessed through Sanger sequencing. A minigene-based splicing assay was also performed. RESULTS The clinical phenotype for all patients was compatible with rod cone degeneration, with the onset during childhood. Whole exome sequencing revealed a homozygous 18 bp intronic deletion (NM_000283.3:c.1921-20_1921-3del) in PDE6B, which co-segregated with disease in 10 affected individuals. In vitro splicing tests showed that this deletion causes aberrant RNA splicing of the gene, leading to the in-frame deletion of 6 codons and, likely, to disease. CONCLUSION Our findings further expand the mutational spectrum of the PDE6B gene.
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Affiliation(s)
- Mukhtar Ullah
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Atta Ur Rehman
- Department of Zoology, Faculty of Biological and Health Sciences, Hazara University Mansehra, Mansehra, Pakistan
| | - Marc Folcher
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
| | - Adnan Ullah
- Department of Zoology, Islamia College Peshawar, Peshawar, Pakistan
| | - Faisal Usman
- Department of Biotechnology and Genetic Engineering, Faculty of Biological and Health Sciences, Hazara University Mansehra, Mansehra, Pakistan
| | - Abdur Rashid
- Department of Higher Education, Archives and Libraries Peshawar, Peshawar, Pakistan
| | - Bilal Khan
- Medical Teaching Institution Khyber Teaching Hospital Peshawar, Peshawar, Pakistan
| | - Mathieu Quinodoz
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
| | - Muhammad Ansar
- Department of Ophthalmology, Jules Gonin Eye Hospital, Fondation Asile Des Aveugles, University of Lausanne, Lausanne, Switzerland
- Advanced Molecular Genetics and Genomics Disease Research and Treatment Centre, Dow University of Health Sciences, Karachi, Pakistan
| | - Carlo Rivolta
- Institute of Molecular and Clinical Ophthalmology Basel (IOB), Basel, Switzerland
- Department of Ophthalmology, University of Basel, Basel, Switzerland
- Department of Genetics and Genome Biology, University of Leicester, Leicester, UK
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Amaratunga SA, Tayeb TH, Dusatkova P, Pruhova S, Lebl J. Invaluable Role of Consanguinity in Providing Insight into Paediatric Endocrine Conditions: Lessons Learnt from Congenital Hyperinsulinism, Monogenic Diabetes, and Short Stature. Horm Res Paediatr 2022; 95:1-11. [PMID: 34847552 DOI: 10.1159/000521210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 11/18/2021] [Indexed: 11/19/2022] Open
Abstract
Consanguineous families have often played a role in the discovery of novel genes, especially in paediatric endocrinology. At this time, it has been estimated that over 8.5% of all children worldwide have consanguineous parents. Consanguinity is linked to demographic, cultural, and religious practises and is more common in some areas around the world than others. In children with endocrine conditions from consanguineous families, there is a greater probability that a single-gene condition with autosomal recessive inheritance is causative. From 1966 and the first description of Laron syndrome, through the discovery of the first KATP channel genes ABCC8 and KCNJ11 causing congenital hyperinsulinism (CHI) in the 1990s, to recent discoveries of mutations in YIPF5 as the first cause of monogenic diabetes due to the disruption of the endoplasmic reticulum (ER)-to-Golgi trafficking in the β-cell and increased ER stress; positive genetic findings in children from consanguinity have been important in elucidating novel genes and mechanisms of disease, thereby expanding knowledge into disease pathophysiology. The aim of this narrative review was to shed light on the lessons learned from consanguineous pedigrees with the help of 3 fundamental endocrine conditions that represent an evolving spectrum of pathophysiological complexity - from CHI, a typically single-cell condition, to monogenic diabetes which presents with uniform biochemical parameters (hyperglycaemia and glycosuria), despite varying aetiologies, up to the genetic regulation of human growth - the most complex developmental phenomenon.
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Affiliation(s)
- Shenali Anne Amaratunga
- Department of Paediatrics, 2nd Faculty of Medicine, Charles University in Prague, Prague, Czechia
| | - Tara Hussein Tayeb
- Department of Paediatrics, Sulaymani University, College of Medicine, Sulaymani, Iraq
| | - Petra Dusatkova
- Department of Paediatrics, 2nd Faculty of Medicine, Charles University in Prague, Prague, Czechia
| | - Stepanka Pruhova
- Department of Paediatrics, 2nd Faculty of Medicine, Charles University in Prague, Prague, Czechia
| | - Jan Lebl
- Department of Paediatrics, 2nd Faculty of Medicine, Charles University in Prague, Prague, Czechia
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Lin S, Harlalka GV, Hameed A, Reham HM, Yasin M, Muhammad N, Khan S, Baple EL, Crosby AH, Saleha S. Novel mutations in ALDH1A3 associated with autosomal recessive anophthalmia/microphthalmia, and review of the literature. BMC Med Genet 2018; 19:160. [PMID: 30200890 PMCID: PMC6131798 DOI: 10.1186/s12881-018-0678-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 09/02/2018] [Indexed: 11/10/2022]
Abstract
BACKGROUND Autosomal recessive anophthalmia and microphthalmia are rare developmental eye defects occurring during early fetal development. Syndromic and non-syndromic forms of anophthalmia and microphthalmia demonstrate extensive genetic and allelic heterogeneity. To date, disease mutations have been identified in 29 causative genes associated with anophthalmia and microphthalmia, with autosomal dominant, autosomal recessive and X-linked inheritance patterns described. Biallelic ALDH1A3 gene variants are the leading genetic causes of autosomal recessive anophthalmia and microphthalmia in countries with frequent parental consanguinity. METHODS This study describes genetic investigations in two consanguineous Pakistani families with a total of seven affected individuals with bilateral non-syndromic clinical anophthalmia. RESULTS Using whole exome and Sanger sequencing, we identified two novel homozygous ALDH1A3 sequence variants as likely responsible for the condition in each family; missense mutation [NM_000693.3:c.1240G > C, p.Gly414Arg; Chr15:101447332G > C (GRCh37)] in exon 11 (family 1), and, a frameshift mutation [NM_000693.3:c.172dup, p.Glu58Glyfs*5; Chr15:101425544dup (GRCh37)] in exon 2 predicted to result in protein truncation (family 2). CONCLUSIONS This study expands the molecular spectrum of pathogenic ALDH1A3 variants associated with anophthalmia and microphthalmia, and provides further insight of the key role of the ALDH1A3 in human eye development.
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Affiliation(s)
- Siying Lin
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Gaurav V Harlalka
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Abdul Hameed
- Institute of Biomedical and Genetic Engineering (IBGE), Islamabad, 44000, Pakistan
| | - Hadia Moattar Reham
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Muhammad Yasin
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Noor Muhammad
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Saadullah Khan
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat, Khyber Pakhtunkhwa, 26000, Pakistan
| | - Emma L Baple
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Andrew H Crosby
- Medical Research, RILD Wellcome Wolfson Centre (Level 4), Royal Devon and Exeter NHS Foundation Trust, Exeter, Devon, EX2 5DW, UK
| | - Shamim Saleha
- Department of Biotechnology and Genetic Engineering, Kohat University of Science and Technology (KUST), Kohat, Khyber Pakhtunkhwa, 26000, Pakistan.
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