1
|
Susgun S, Kesim Y, Khalilov D, Sirin NG, Gezegen H, Salman B, Yucesan E, Gokcay G, Korbeyli HK, Balci MC, Iseri SAU, Baykan B, Bebek N. Reanalysis of exome sequencing data reveals a treatable neurometabolic origin in two previously undiagnosed siblings with neurodevelopmental disorder. Neurol Sci 2023:10.1007/s10072-023-06699-8. [PMID: 36849695 DOI: 10.1007/s10072-023-06699-8] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 02/17/2023] [Indexed: 03/01/2023]
Abstract
Neurodevelopmental disorders (NDDs) have broad heterogeneity both clinically and genetically. Inborn errors of metabolism can be one of the reasons of neurodevelopmental disruption causing specific NDDs. Although there is tremendous advance in molecular identification via next-generation sequencing (NGS), there are still many unsolved patients with NDD. Reanalysis of NGS data with different pipelines can at least partially accomplish this challenge. Herein, we report clinic and genetic components of an adult sib-pair with an undiagnosed NDD condition, which has been solved through reanalysis of whole-exome sequencing (WES). Parallel analysis of SNP-based genotyping and WES was performed to focus on variants only in loci with positive logarithm of the odds scores. WES data was analyzed through three different pipelines with two distinct bed files. Reanalysis of WES data led us to detect a homozygous FOLR1 variant (ENST00000393676.5:c.610C > T, p.(Arg204Ter), rs952165627) in the affected sib-pair. Surprisingly, the variant could not be detected in the first analysis as the variant region is not included in the first bed file which may frequently be used. Biochemical tests of CSF have confirmed the genetic analysis, CSF folic acid levels were detected low in sib-pair, and intravenous folinic acid treatment improved the disease course for the first 6 months of follow-up even at late diagnosis age. Although combined analysis of SNP-based genotyping and WES is a powerful tool to reveal the genetic components of heterogeneous diseases, reanalysis of genome data still should be considered in unsolved patients. Also, biochemical screening helps us to decipher undiagnosed NDD that may be a treatable neurometabolic condition.
Collapse
Affiliation(s)
- Seda Susgun
- Department of Genetics, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
- Graduate School of Health Sciences, Istanbul University, Istanbul, Turkey
- Department of Medical Biology, Faculty of Medicine, Bezmialem Vakif University, Istanbul, Turkey
| | - Yesim Kesim
- Department of Genetics, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
- Graduate School of Health Sciences, Istanbul University, Istanbul, Turkey
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brooks University, Oxford, UK
| | - Dovlat Khalilov
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Nermin Gorkem Sirin
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Hasim Gezegen
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Baris Salman
- Department of Genetics, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
- Graduate School of Health Sciences, Istanbul University, Istanbul, Turkey
| | - Emrah Yucesan
- Department of Neurogenetics, Institute of Neurological Sciences, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Gulden Gokcay
- Department of Pediatrics, Division of Pediatric Nutrition and Metabolism, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Huseyin Kutay Korbeyli
- Department of Pediatrics, Division of Pediatric Nutrition and Metabolism, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Mehmet Cihan Balci
- Department of Pediatrics, Division of Pediatric Nutrition and Metabolism, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Sibel Aylin Ugur Iseri
- Department of Genetics, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey.
| | - Betul Baykan
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Nerses Bebek
- Department of Neurology, Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| |
Collapse
|