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Yoon SY, Kim JS, Park KS. Aberrant Splicing in PKD2 in a Family of Korean Patients With Autosomal Dominant Polycystic Kidney Disease. Ann Lab Med 2024; 44:621-624. [PMID: 39169606 PMCID: PMC11375193 DOI: 10.3343/alm.2024.0221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2024] [Revised: 07/04/2024] [Accepted: 08/08/2024] [Indexed: 08/23/2024] Open
Affiliation(s)
- Soo-Young Yoon
- Division of Nephrology, Department of Internal Medicine, Kyung Hee University College of Medicine, Kyung Hee University Medical Center, Seoul, Korea
| | - Jin Sug Kim
- Division of Nephrology, Department of Internal Medicine, Kyung Hee University College of Medicine, Kyung Hee University Medical Center, Seoul, Korea
| | - Kyung Sun Park
- Department of Laboratory Medicine, Kyung Hee University College of Medicine, Kyung Hee University Medical Center, Seoul, Korea
- Rare Disease Center, Kyung Hee University College of Medicine, Kyung Hee University Medical Center, Seoul, Korea
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2
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Beaman MM, Yin W, Smith AJ, Sears PR, Leigh MW, Ferkol TW, Kearney B, Olivier KN, Kimple AJ, Clarke S, Huggins E, Nading E, Jung SH, Iyengar AK, Zou X, Dang H, Barrera A, Majoros WH, Rehder CW, Reddy TE, Ostrowski LE, Allen AS, Knowles MR, Zariwala MA, Crawford GE. Promoter Deletion Leading to Allele Specific Expression in a Genetically Unsolved Case of Primary Ciliary Dyskinesia. Am J Med Genet A 2024:e63880. [PMID: 39364610 DOI: 10.1002/ajmg.a.63880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Revised: 08/16/2024] [Accepted: 09/02/2024] [Indexed: 10/05/2024]
Abstract
Variation in the non-coding genome represents an understudied mechanism of disease and it remains challenging to predict if single nucleotide variants, small insertions and deletions, or structural variants in non-coding genomic regions will be detrimental. Our approach using complementary RNA-seq and targeted long-read DNA sequencing can prioritize identification of non-coding variants that lead to disease via alteration of gene splicing or expression. We have identified a patient with primary ciliary dyskinesia with a pathogenic coding variant on one allele of the SPAG1 gene, while the second allele appears normal by whole exome sequencing despite an autosomal recessive inheritance pattern. RNA sequencing revealed reduced SPAG1 transcript levels and exclusive allele specific expression of the known pathogenic allele, suggesting the presence of a non-coding variant on the second allele that impacts transcription. Targeted long-read DNA sequencing identified a heterozygous 3 kilobase deletion of the 5' untranslated region of SPAG1, overlapping the promoter and first non-coding exon. This non-coding deletion was missed by whole exome sequencing and gene-specific deletion/duplication analysis, highlighting the importance of investigating the non-coding genome in patients with "missing" disease-causing variation. This paradigm demonstrates the utility of both RNA and long-read DNA sequencing in identifying pathogenic non-coding variants in patients with unexplained genetic disease.
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Affiliation(s)
- M Makenzie Beaman
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, North Carolina, USA
- Medical Scientist Training Program, Duke University, Durham, North Carolina, USA
- University Program in Genetics & Genomics, Duke University, Durham, North Carolina, USA
| | - Weining Yin
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Amanda J Smith
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Patrick R Sears
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Margaret W Leigh
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Thomas W Ferkol
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Brendan Kearney
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | - Kenneth N Olivier
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Adam J Kimple
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Otolaryngology/Head & Neck Surgery, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Shannon Clarke
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | - Erin Huggins
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, North Carolina, USA
| | - Erica Nading
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, North Carolina, USA
| | - Seung-Hye Jung
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, North Carolina, USA
| | - Apoorva K Iyengar
- University Program in Genetics & Genomics, Duke University, Durham, North Carolina, USA
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | - Xue Zou
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
- Program in Computational Biology & Bioinformatics, Duke University, Durham, North Carolina, USA
| | - Hong Dang
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Alejandro Barrera
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | - William H Majoros
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | | | - Timothy E Reddy
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | - Lawrence E Ostrowski
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Andrew S Allen
- Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA
- Center for Statistical Genetics and Genomics, Duke University, Durham, North Carolina, USA
| | - Michael R Knowles
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Maimoona A Zariwala
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
- Department of Pediatrics, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA
| | - Gregory E Crawford
- Department of Pediatrics, Division of Medical Genetics, Duke University, Durham, North Carolina, USA
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3
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Wells JR, Padua MB, Haaning AM, Smith AM, Morris SA, Tariq M, Ware SM. Non-coding cause of congenital heart defects: Abnormal RNA splicing with multiple isoforms as a mechanism for heterotaxy. HGG ADVANCES 2024; 5:100353. [PMID: 39275801 DOI: 10.1016/j.xhgg.2024.100353] [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: 05/21/2024] [Revised: 09/10/2024] [Accepted: 09/10/2024] [Indexed: 09/16/2024] Open
Abstract
Heterotaxy is a disorder characterized by severe congenital heart defects (CHDs) and abnormal left-right patterning in other thoracic or abdominal organs. Clinical and research-based genetic testing has previously focused on evaluation of coding variants to identify causes of CHDs, leaving non-coding causes of CHDs largely unknown. Variants in the transcription factor zinc finger of the cerebellum 3 (ZIC3) cause X-linked heterotaxy. We identified an X-linked heterotaxy pedigree without a coding variant in ZIC3. Whole-genome sequencing revealed a deep intronic variant (ZIC3 c.1224+3286A>G) predicted to alter RNA splicing. An in vitro minigene splicing assay confirmed the variant acts as a cryptic splice acceptor. CRISPR-Cas9 served to introduce the ZIC3 c.1224+3286A>G variant into human embryonic stem cells demonstrating pseudoexon inclusion caused by the variant. Surprisingly, Sanger sequencing of the resulting ZIC3 c.1224+3286A>G amplicons revealed several isoforms, many of which bypass the normal coding sequence of the third exon of ZIC3, causing a disruption of a DNA-binding domain and a nuclear localization signal. Short- and long-read mRNA sequencing confirmed these initial results and identified additional splicing patterns. Assessment of four isoforms determined abnormal functions in vitro and in vivo while treatment with a splice-blocking morpholino partially rescued ZIC3. These results demonstrate that pseudoexon inclusion in ZIC3 can cause heterotaxy and provide functional validation of non-coding disease causation. Our results suggest the importance of non-coding variants in heterotaxy and the need for improved methods to identify and classify non-coding variation that may contribute to CHDs.
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Affiliation(s)
- John R Wells
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Maria B Padua
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Allison M Haaning
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Amanda M Smith
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Shaine A Morris
- Department of Pediatrics, Division of Pediatric Cardiology, Baylor College of Medicine and Texas Children's Hospital, Houston, TX 77030, USA
| | - Muhammad Tariq
- Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Stephanie M Ware
- Department of Medical & Molecular Genetics, Indiana University School of Medicine, Indianapolis, IN 46202, USA; Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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4
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Bockenhauer D, Stanescu H. Distal renal tubular acidosis and WDR72: some answers, more questions. Pediatr Nephrol 2024:10.1007/s00467-024-06504-4. [PMID: 39237640 DOI: 10.1007/s00467-024-06504-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2024] [Revised: 08/10/2024] [Accepted: 08/12/2024] [Indexed: 09/07/2024]
Affiliation(s)
- Detlef Bockenhauer
- Department of Paediatric Nephrology, UZ Leuven and Cellular and Molecular Physiology, KUL, Heerestrat 49, Leuven, Belgium.
- UCL Department of Renal Medicine, London, UK.
- Paediatric Nephrology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
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5
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Hobara T, Higuchi Y, Yoshida M, Suehara M, Ando M, Yuan JH, Yoshimura A, Kojima F, Matsuura E, Okamoto Y, Mitsui J, Tsuji S, Takashima H. Genetic and pathophysiological insights from autopsied patient with primary familial brain calcification: novel MYORG variants and astrocytic implications. Acta Neuropathol Commun 2024; 12:136. [PMID: 39180105 PMCID: PMC11342542 DOI: 10.1186/s40478-024-01847-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2024] [Accepted: 08/04/2024] [Indexed: 08/26/2024] Open
Abstract
Primary familial brain calcification (PFBC) is a genetic neurological disorder characterized by symmetric brain calcifications that manifest with variable neurological symptoms. This study aimed to explore the genetic basis of PFBC and elucidate the underlying pathophysiological mechanisms. Six patients from four pedigrees with brain calcification were enrolled. Whole-exome sequencing identified two novel homozygous variants, c.488G > T (p.W163L) and c.2135G > A (p.W712*), within the myogenesis regulating glycosidase (MYORG) gene. Cerebellar ataxia (n = 5) and pyramidal signs (n = 4) were predominant symptoms, with significant clinical heterogeneity noted even within the same family. An autopsy of one patient revealed extensive brainstem calcifications, sparing the cerebral cortex, and marked by calcifications predominantly in capillaries and arterioles. The pathological study suggested morphological alterations characterized by shortened foot processes within astrocytes in regions with pronounced calcification and decreased immunoreactivity of AQP4. The morphology of astrocytes in regions without calcification remains preserved. Neuronal loss and gliosis were observed in the basal ganglia, thalamus, brainstem, cerebellum, and dentate nucleus. Notably, olivary hypertrophy, a previously undescribed feature in MYORG-PFBC, was discovered. Neuroimaging showed reduced blood flow in the cerebellum, highlighting the extent of cerebellar involvement. Among perivascular cells constituting the blood-brain barrier (BBB) and neurovascular unit, MYORG is most highly expressed in astrocytes. Astrocytes are integral components of the BBB, and their dysfunction can precipitate BBB disruption, potentially leading to brain calcification and subsequent neuronal loss. This study presents two novel homozygous variants in the MYORG gene and highlights the pivotal role of astrocytes in the development of brain calcifications, providing insights into the pathophysiological mechanisms underlying PFBC associated with MYORG variants.
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Affiliation(s)
- Takahiro Hobara
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yujiro Higuchi
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
| | - Mari Yoshida
- Department of Neuropathology, Institute for Medical Science of Aging, Aichi Medical University, Aichi, Japan
| | - Masahito Suehara
- Department of Neurology, Fujimoto General Hospital, Miyazaki, Japan
| | - Masahiro Ando
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Jun-Hui Yuan
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Akiko Yoshimura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Fumikazu Kojima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Eiji Matsuura
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
| | - Yuji Okamoto
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
- Department of Physical Therapy, School of Health Sciences, Faculty of Medicine, Kagoshima University, Kagoshima, Japan
| | - Jun Mitsui
- Department of Precision Medicine Neurology, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Shoji Tsuji
- Institute of Medical Genomics, International University of Health and Welfare, 4-3, Kozunomori, Chiba, Japan
- Department of Neurology, The University of Tokyo Hospital, 7-3-1 Hongo, Bunkyo-Ku, Tokyo, Japan
| | - Hiroshi Takashima
- Department of Neurology and Geriatrics, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan
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Riaño-Moreno JC, González-Clavijo AM, Torres J. WC, Medina B. VL, Romero-Rojas AE, Vieda-Celemin I, Avila-Moya JA, Baron-Cardona JA, Bravo-Patiño JP, Torres-Zambrano OS, Maya LFF. Case report: Comprehensive follow-up of a Colombian family carrying a novel MEN1 variant linked to a rare ACTH-producing pancreatic neuroendocrine carcinoma. Front Endocrinol (Lausanne) 2024; 15:1398436. [PMID: 39104820 PMCID: PMC11298364 DOI: 10.3389/fendo.2024.1398436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2024] [Accepted: 07/08/2024] [Indexed: 08/07/2024] Open
Abstract
Background Multiple Endocrine Neoplasia type 1 (MEN1) is an autosomal dominant disorder marked by pathogenic variants in the MEN1 tumor suppressor gene, leading to tumors in the parathyroid glands, pancreas, and pituitary. The occurrence of ACTH-producing pancreatic neuroendocrine carcinoma is exceedingly rare in MEN1. Case presentation This report details a Colombian family harboring a novel MEN1 variant identified through genetic screening initiated by the index case. Affected family members exhibited primary hyperparathyroidism (PHPT) symptoms from their 20s to 50s. Uniquely, the index case developed an ACTH-secreting pancreatic neuroendocrine carcinoma, a rarity in MEN1 syndromes. Proactive screening enabled the early detection of pituitary neuroendocrine tumors (PitNETs) as microadenomas in two carriers, with subsequent surgical or pharmacological intervention based on the clinical presentation. Conclusion Our findings underscore the significance of cascade screening in facilitating the early diagnosis and individualized treatment of MEN1, contributing to better patient outcomes. Additionally, this study brings to light a novel presentation of ACTH-producing pancreatic neuroendocrine carcinoma within the MEN1 spectrum, expanding our understanding of the disease's manifestations.
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Affiliation(s)
- Julián C. Riaño-Moreno
- Department of Pathology and Molecular Oncology, Instituto Nacional de Cancerología, Bogotá, Colombia
- Faculty of Medicine, Universidad Cooperativa de Colombia, Villavicencio, Colombia
- Department of Bioethics, Universidad El Bosque, Bogotá, Colombia
| | - Angélica María González-Clavijo
- Department of Physiological Sciences, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
- Endocrine Oncology Unit, Instituto Nacional de Cancerología, Bogotá, Colombia
| | - William C. Torres J.
- Department of Pathology and Molecular Oncology, Instituto Nacional de Cancerología, Bogotá, Colombia
| | - Vilma L. Medina B.
- Department of Pathology and Molecular Oncology, Instituto Nacional de Cancerología, Bogotá, Colombia
| | | | - Isabella Vieda-Celemin
- Department of Physiological Sciences, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Jordan A. Avila-Moya
- Department of Physiological Sciences, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Johan A. Baron-Cardona
- Department of Physiological Sciences, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Juan P. Bravo-Patiño
- Department of Physiological Sciences, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
| | - Oscar S. Torres-Zambrano
- Department of Physiological Sciences, Faculty of Medicine, Universidad Nacional de Colombia, Bogotá, Colombia
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Yoneno S, Yamamoto K, Tabata K, Shimizu-Motohashi Y, Tomita A, Hayashi T, Maki H, Sato N, Inoue K, Saitsu H, Komaki H. A novel heterozygous TMEM63A variant in a familial case with early onset nystagmus, severe hypomyelination, and a favorable adult prognosis. J Hum Genet 2024:10.1038/s10038-024-01268-z. [PMID: 38951194 DOI: 10.1038/s10038-024-01268-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/18/2024] [Accepted: 06/20/2024] [Indexed: 07/03/2024]
Abstract
Heterozygous transmembrane protein 63A (TMEM63A) variants cause transient infantile hypomyelinating leukodystrophy-19, which features remarkable natural resolution of clinical and imaging findings during childhood. Previous reports have mainly described de novo variants lacking detailed familial cases. Herein, we describe the clinical course of familial cases with a TMEM63A variant. A 5-month-old girl presented with nystagmus, global hypotonia, and difficulty swallowing since birth. Brain magnetic resonance imaging at 1.5 and 5 months revealed diffuse hypomyelination. Her mother, maternal aunt, and grandfather had nystagmus and motor developmental delays in infancy, which resolved spontaneously during childhood. Compared with these cases, the proband's motor developmental delay was profound, and she was the only one with feeding difficulties, necessitating nasogastric tube feeding. Genetic testing revealed a heterozygous TMEM63A variant (NM_014698.3:c.1658G>A, p.(Gly553Asp)) in the proband and her family. This is the first three-generation familial report of a TMEM63A variant that provides insight into its history and heterogeneity.
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Affiliation(s)
- Shota Yoneno
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Kaoru Yamamoto
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan.
| | - Kenshiro Tabata
- Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Yuko Shimizu-Motohashi
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Ayaka Tomita
- Department of Neonatology, Toho University Omori Medical Center, Tokyo, Japan
| | - Taiju Hayashi
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Hiroyuki Maki
- Department of Radiology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Noriko Sato
- Department of Radiology, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Ken Inoue
- Department of Mental Retardation and Birth Defect Research, National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan
| | - Hirotomo Saitsu
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Hirofumi Komaki
- Department of Child Neurology, National Center of Neurology and Psychiatry, Tokyo, Japan
- Translational Medical Center, National Center of Neurology and Psychiatry, Tokyo, Japan
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8
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D'Souza P, Farmer C, Johnston JM, Han ST, Adams D, Hartman AL, Zein W, Huryn LA, Solomon B, King K, Jordan CP, Myles J, Nicoli ER, Rothermel CE, Mojica Algarin Y, Huang R, Quimby R, Zainab M, Bowden S, Crowell A, Buckley A, Brewer C, Regier DS, Brooks BP, Acosta MT, Baker EH, Vézina G, Thurm A, Tifft CJ. GM1 gangliosidosis type II: Results of a 10-year prospective study. Genet Med 2024; 26:101144. [PMID: 38641994 PMCID: PMC11348282 DOI: 10.1016/j.gim.2024.101144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 04/10/2024] [Accepted: 04/11/2024] [Indexed: 04/21/2024] Open
Abstract
PURPOSE GM1 gangliosidosis (GM1) a lysosomal disorder caused by pathogenic variants in GLB1, is characterized by relentless neurodegeneration. There are no approved treatments. METHODS Forty-one individuals with type II (late-infantile and juvenile) GM1 participated in a single-site prospective observational study. RESULTS Classification of 37 distinct variants using American College of Medical Genetics and Genomics criteria resulted in the upgrade of 6 and the submission of 4 new variants. In contrast to type I infantile disease, children with type II had normal or near normal hearing and did not have cherry-red maculae or hepatosplenomegaly. Some older children with juvenile onset disease developed thickened aortic and/or mitral valves. Serial magnetic resonance images demonstrated progressive brain atrophy, more pronounced in late infantile patients. Magnetic resonance spectroscopy showed worsening elevation of myo-inositol and deficit of N-acetyl aspartate that were strongly correlated with scores on the Vineland Adaptive Behavior Scale, progressing more rapidly in late infantile compared with juvenile onset disease. CONCLUSION Serial phenotyping of type II GM1 patients expands the understanding of disease progression and clarifies common misconceptions about type II patients; these are pivotal steps toward more timely diagnosis and better supportive care. The data amassed through this 10-year effort will serve as a robust comparator for ongoing and future therapeutic trials.
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Affiliation(s)
- Precilla D'Souza
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Cristan Farmer
- Neurodevelopmental and Behavioral Phenotyping Service, National Institute of Mental Health, Bethesda, MD
| | - Jean M Johnston
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Sangwoo T Han
- Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - David Adams
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD
| | - Adam L Hartman
- Division of Clinical Research, National Institute of Neurological Disorders and Stroke, Bethesda, MD
| | - Wadih Zein
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, Bethesda, MD
| | - Laryssa A Huryn
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, Bethesda, MD
| | - Beth Solomon
- Rehabilitation Medicine Department, Warren C. Magnuson Clinical Research Center, Bethesda, MD
| | - Kelly King
- Neurology Branch, National Institute on Deafness and Other Communication Disorders, Bethesda, MD
| | | | - Jennifer Myles
- Nutrition Department, Warren C. Magnuson Clinical Research Center, Bethesda, MD
| | - Elena-Raluca Nicoli
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Caroline E Rothermel
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Yoliann Mojica Algarin
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Reyna Huang
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Rachel Quimby
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Mosufa Zainab
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Sarah Bowden
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Anna Crowell
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD
| | - Ashura Buckley
- Sleep and Neurodevelopment Service, National Institute of Mental Health, Bethesda, MD
| | - Carmen Brewer
- Neurology Branch, National Institute on Deafness and Other Communication Disorders, Bethesda, MD
| | - Debra S Regier
- Genetics and Metabolism, Children's National Hospital, Washington, DC
| | - Brian P Brooks
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, Bethesda, MD
| | - Maria T Acosta
- Undiagnosed Disease Program, National Human Genome Research Institute, Bethesda, MD
| | - Eva H Baker
- Department of Radiology and Imaging Sciences, National Institutes of Health Clinical Center, Bethesda, MD
| | - Gilbert Vézina
- Program in Neuroradiology and Program in Radiology, Children's National Hospital, Washington, DC; Radiology and Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Audrey Thurm
- Neurodevelopmental and Behavioral Phenotyping Service, National Institute of Mental Health, Bethesda, MD
| | - Cynthia J Tifft
- Office of the Clinical Director, National Human Genome Research Institute, Bethesda, MD; Medical Genetics Branch, National Human Genome Research Institute, Bethesda, MD.
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9
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Chong JX, Berger SI, Baxter S, Smith E, Xiao C, Calame DG, Hawley MH, Rivera-Munoz EA, DiTroia S, Bamshad MJ, Rehm HL. Considerations for reporting variants in novel candidate genes identified during clinical genomic testing. Genet Med 2024; 26:101199. [PMID: 38944749 DOI: 10.1016/j.gim.2024.101199] [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: 02/09/2024] [Revised: 06/18/2024] [Accepted: 06/21/2024] [Indexed: 07/01/2024] Open
Abstract
Since the first novel gene discovery for a Mendelian condition was made via exome sequencing, the rapid increase in the number of genes known to underlie Mendelian conditions coupled with the adoption of exome (and more recently, genome) sequencing by diagnostic testing labs has changed the landscape of genomic testing for rare diseases. Specifically, many individuals suspected to have a Mendelian condition are now routinely offered clinical ES. This commonly results in a precise genetic diagnosis but frequently overlooks the identification of novel candidate genes. Such candidates are also less likely to be identified in the absence of large-scale gene discovery research programs. Accordingly, clinical laboratories have both the opportunity, and some might argue a responsibility, to contribute to novel gene discovery, which should, in turn, increase the diagnostic yield for many conditions. However, clinical diagnostic laboratories must necessarily balance priorities for throughput, turnaround time, cost efficiency, clinician preferences, and regulatory constraints and often do not have the infrastructure or resources to effectively participate in either clinical translational or basic genome science research efforts. For these and other reasons, many laboratories have historically refrained from broadly sharing potentially pathogenic variants in novel genes via networks such as Matchmaker Exchange, much less reporting such results to ordering providers. Efforts to report such results are further complicated by a lack of guidelines for clinical reporting and interpretation of variants in novel candidate genes. Nevertheless, there are myriad benefits for many stakeholders, including patients/families, clinicians, and researchers, if clinical laboratories systematically and routinely identify, share, and report novel candidate genes. To facilitate this change in practice, we developed criteria for triaging, sharing, and reporting novel candidate genes that are most likely to be promptly validated as underlying a Mendelian condition and translated to use in clinical settings.
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Affiliation(s)
- Jessica X Chong
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA; Brotman-Baty Institute for Precision Medicine, Seattle, WA.
| | - Seth I Berger
- Center for Genetic Medicine Research, Children's National Research Institute, Washington, DC
| | - Samantha Baxter
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA
| | - Erica Smith
- Department of Clinical Diagnostics, Ambry Genetics, Aliso Viejo, CA
| | - Changrui Xiao
- Department of Neurology, University of California Irvine, Orange, CA
| | - Daniel G Calame
- Department of Pediatrics, Division of Pediatric Neurology and Developmental Neurosciences, Baylor College of Medicine, Houston, TX
| | | | | | - Stephanie DiTroia
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA
| | - Michael J Bamshad
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Seattle, WA; Brotman-Baty Institute for Precision Medicine, Seattle, WA; Department of Pediatrics, Division of Genetic Medicine, Seattle Children's Hospital, Seattle, WA
| | - Heidi L Rehm
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA; Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA
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Chong JX, Berger SI, Baxter S, Smith E, Xiao C, Calame DG, Hawley MH, Rivera-Munoz EA, DiTroia S, Bamshad MJ, Rehm HL. Considerations for reporting variants in novel candidate genes identified during clinical genomic testing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.579012. [PMID: 38370830 PMCID: PMC10871197 DOI: 10.1101/2024.02.05.579012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Since the first novel gene discovery for a Mendelian condition was made via exome sequencing (ES), the rapid increase in the number of genes known to underlie Mendelian conditions coupled with the adoption of exome (and more recently, genome) sequencing by diagnostic testing labs has changed the landscape of genomic testing for rare disease. Specifically, many individuals suspected to have a Mendelian condition are now routinely offered clinical ES. This commonly results in a precise genetic diagnosis but frequently overlooks the identification of novel candidate genes. Such candidates are also less likely to be identified in the absence of large-scale gene discovery research programs. Accordingly, clinical laboratories have both the opportunity, and some might argue a responsibility, to contribute to novel gene discovery which should in turn increase the diagnostic yield for many conditions. However, clinical diagnostic laboratories must necessarily balance priorities for throughput, turnaround time, cost efficiency, clinician preferences, and regulatory constraints, and often do not have the infrastructure or resources to effectively participate in either clinical translational or basic genome science research efforts. For these and other reasons, many laboratories have historically refrained from broadly sharing potentially pathogenic variants in novel genes via networks like Matchmaker Exchange, much less reporting such results to ordering providers. Efforts to report such results are further complicated by a lack of guidelines for clinical reporting and interpretation of variants in novel candidate genes. Nevertheless, there are myriad benefits for many stakeholders, including patients/families, clinicians, researchers, if clinical laboratories systematically and routinely identify, share, and report novel candidate genes. To facilitate this change in practice, we developed criteria for triaging, sharing, and reporting novel candidate genes that are most likely to be promptly validated as underlying a Mendelian condition and translated to use in clinical settings.
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Affiliation(s)
- Jessica X. Chong
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, 1959 NE Pacific Street, Box 357371, Seattle, WA, 98195, USA
- Brotman-Baty Institute for Precision Medicine, 1959 NE Pacific Street, Box 357657, Seattle, WA, 98195, USA
| | - Seth I. Berger
- Center for Genetic Medicine Research, Children’s National Research Institute, 111 Michigan Ave, NW, Washington, DC, 20010, USA
| | - Samantha Baxter
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, 415 Main St, Cambridge, MA, 02141, USA
| | - Erica Smith
- Department of Clinical Diagnostics, Ambry Genetics, 15 Argonaut, Aliso Viejo, CA, 92656, USA
| | - Changrui Xiao
- Department of Neurology, University of California Irvine, 200 South Manchester Ave. St 206E, Orange, CA, 92868, USA
| | - Daniel G. Calame
- Department of Pediatrics, Division of Pediatric Neurology and Developmental Neurosciences, Baylor College of Medicine, One Baylor Plaza, Houston, TX, 77030, USA
| | - Megan H. Hawley
- Clinical Operations, Invitae, 485F US-1 Suite 110, Iselin, NJ, 08830, USA
| | - E. Andres Rivera-Munoz
- Department of Molecular and Human Genetics, Baylor College of Medicine, 1 Baylor Plaza T605, Houston, TX, 77030, USA
| | - Stephanie DiTroia
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, 415 Main St, Cambridge, MA, 02141, USA
| | | | - Michael J. Bamshad
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, 1959 NE Pacific Street, Box 357371, Seattle, WA, 98195, USA
- Brotman-Baty Institute for Precision Medicine, 1959 NE Pacific Street, Box 357657, Seattle, WA, 98195, USA
- Department of Pediatrics, Division of Genetic Medicine, Seattle Children’s Hospital, Seattle, WA, 98195, USA
| | - Heidi L. Rehm
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, 415 Main St, Cambridge, MA, 02141, USA
- Center for Genomic Medicine, Massachusetts General Hospital, 185 Cambridge St, Boston, MA, 02114, USA
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Boysen KB, Tümer Z, Bach-Holm D, Bisgaard AM, Kessel L. Microphthalmia and congenital cataract in two patients with Stickler syndrome type II: a case report. Ophthalmic Genet 2024; 45:313-318. [PMID: 38299479 DOI: 10.1080/13816810.2024.2309700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 01/12/2024] [Accepted: 01/19/2024] [Indexed: 02/02/2024]
Abstract
BACKGROUND Stickler syndrome (STL) is a collagenopathy caused by pathogenic variants in collagen-coding genes, mainly COL2A1 or COL11A1 associated with Stickler syndrome type 1 (STL1) or type 2 (STL2), respectively. Affected individuals manifest ocular, auditory, articular, and craniofacial findings in varying degrees. Previous literature and case reports describe high variability in clinical findings for patients with STL. With this case report, we broaden the clinical spectrum of the phenotype. MATERIALS AND METHODS Case report on two members of a family (mother and son) including clinical examination and genetic testing using targeted trio whole exome sequencing (trio-WES). RESULTS A boy and his mother presented with microphthalmia, congenital cataract, ptosis, and moderate-to-severe sensorineural hearing loss. Trio-WES found a novel heterozygote missense variant, c.4526A>G; p(Gln1509Arg) in COL11A1 in both affected individuals. CONCLUSIONS We report a previously undescribed phenotype associated with a COL11A1-variant in a mother and son, expanding the spectrum for phenotype-genotype correlation in STL2, presenting with microphthalmia, congenital cataract, and ptosis not normally associated with Stickler syndrome.
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Affiliation(s)
- Kirstine Bolette Boysen
- Department of Ophthalmology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Zeynep Tümer
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
- Department of Clinical Genetics, Kennedy Center, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Daniella Bach-Holm
- Department of Ophthalmology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Anne-Marie Bisgaard
- Department of Paediatrics and Adolescent Medicine, Center for Rare Disease, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
| | - Line Kessel
- Department of Ophthalmology, Copenhagen University Hospital - Rigshospitalet, Copenhagen, Denmark
- Department of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Basel-Salmon L. Phenotypic compatibility and specificity in genomic variant classification. Eur J Hum Genet 2024; 32:471-473. [PMID: 38351291 PMCID: PMC11061282 DOI: 10.1038/s41431-024-01554-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 01/26/2024] [Indexed: 05/02/2024] Open
Affiliation(s)
- Lina Basel-Salmon
- Raphael Recanati Genetic Institute, Rabin Medical Center - Beilinson Hospital, Petach Tikva, 4941492, Israel.
- Faculty of Medicine, Tel Aviv University, Tel Aviv, 6997801, Israel.
- Felsenstein Medical Research Center, Petach Tikva, 4920235, Israel.
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13
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Goldstein J, Thomas-Wilson A, Groopman E, Aggarwal V, Bianconi S, Fernandez R, Hart K, Longo N, Liang N, Reich D, Wallis H, Weaver M, Young S, Mercimek-Andrews S. ClinGen variant curation expert panel recommendations for classification of variants in GAMT, GATM and SLC6A8 for cerebral creatine deficiency syndromes. Mol Genet Metab 2024; 142:108362. [PMID: 38452609 DOI: 10.1016/j.ymgme.2024.108362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 02/26/2024] [Accepted: 02/27/2024] [Indexed: 03/09/2024]
Abstract
Cerebral creatine deficiency syndromes (CCDS) are inherited metabolic phenotypes of creatine synthesis and transport. There are two enzyme deficiencies, guanidinoacetate methyltransferase (GAMT), encoded by GAMT and arginine-glycine amidinotransferase (AGAT), encoded by GATM, which are involved in the synthesis of creatine. After synthesis, creatine is taken up by a sodium-dependent membrane bound creatine transporter (CRTR), encoded by SLC6A8, into all organs. Creatine uptake is very important especially in high energy demanding organs such as the brain, and muscle. To classify the pathogenicity of variants in GAMT, GATM, and SLC6A8, we developed the CCDS Variant Curation Expert Panel (VCEP) in 2018, supported by The Clinical Genome Resource (ClinGen), a National Institutes of Health (NIH)-funded resource. We developed disease-specific variant classification guidelines for GAMT-, GATM-, and SLC6A8-related CCDS, adapted from the American College of Medical Genetics/Association of Molecular Pathology (ACMG/AMP) variant interpretation guidelines. We applied specific variant classification guidelines to 30 pilot variants in each of the three genes that have variants associated with CCDS. Our CCDS VCEP was approved by the ClinGen Sequence Variant Interpretation Working Group (SVI WG) and Clinical Domain Oversight Committee in July 2022. We curated 181 variants including 72 variants in GAMT, 45 variants in GATM, and 64 variants in SLC6A8 and submitted these classifications to ClinVar, a public variant database supported by the National Center for Biotechnology Information. Missense variants were the most common variant type in all three genes. We submitted 32 new variants and reclassified 34 variants with conflicting interpretations. We report specific phenotype (PP4) using a points system based on the urine and plasma guanidinoacetate and creatine levels, brain magnetic resonance spectroscopy (MRS) creatine level, and enzyme activity or creatine uptake in fibroblasts ranging from PP4, PP4_Moderate and PP4_Strong. Our CCDS VCEP is one of the first panels applying disease specific variant classification algorithms for an X-linked disease. The availability of these guidelines and classifications can guide molecular genetics and genomic laboratories and health care providers to assess the molecular diagnosis of individuals with a CCDS phenotype.
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Affiliation(s)
- Jennifer Goldstein
- Department of Genetics, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | | | - Emily Groopman
- Children's National Hospital, 111 Michigan Ave NW, Washington, DC, USA
| | - Vimla Aggarwal
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY, USA
| | - Simona Bianconi
- Kaiser Permanente, Southern California Permanente Group, CA, USA
| | - Raquel Fernandez
- American College of Medical Genetics and Genomics, Bethesda, MD, USA
| | - Kim Hart
- Newborn Screening Program, Utah Public Health Laboratory, Department of Health and Human Services, Salt Lake City, UT, USA
| | - Nicola Longo
- Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | | | - Daniel Reich
- Newborn Screening Program, Utah Public Health Laboratory, Department of Health and Human Services, Salt Lake City, UT, USA
| | - Heidi Wallis
- Association for Creatine Deficiencies, Carlsbad, CA, USA
| | - Meredith Weaver
- American College of Medical Genetics and Genomics, Bethesda, MD, USA
| | - Sarah Young
- Department of Pediatrics, Duke University School of Medicine, Durham, NC, USA
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León‐Madero LF, Fregoso‐Ron CH, De León‐Carbajal JC, Valdés‐Miranda JM. Mexican patient with Ellis-van Creveld syndrome and cleft palate: Importance of functional hemizygosity and phenotype expansion. Mol Genet Genomic Med 2024; 12:e2451. [PMID: 38760995 PMCID: PMC11101913 DOI: 10.1002/mgg3.2451] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/21/2024] [Accepted: 04/30/2024] [Indexed: 05/20/2024] Open
Abstract
BACKGROUND Ellis-van Creveld syndrome (EvCS) is a chondroectodermal dysplasia caused by germline pathogenic variants in ciliary complex subunit 1 and 2 genes (EVC, EVC2) on chromosome 4p16.2. This disease has a broad phenotype, and there are few described phenotype-genotype correlations. METHODS Ethical Compliance: Written informed consent was obtained from the parents. Here, we report a genetically confirmed Mexican patient with EvCS having two inherited pathogenic variants in trans in EVC2: c.[1195C>T];[2161delC]. RESULTS This patient allowed a genotypic-phenotypic comparison with another Mexican subject who presented a more attenuated phenotype; furthermore, our patient also presented cleft palate, a rarely reported feature. CONCLUSION Our case shows the importance of comparing functional hemizygosity between patient's phenotypes when they share a variant, and our case also supports the association of alterations in the palate as part of the EvCS phenotype.
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Affiliation(s)
- Luis Felipe León‐Madero
- Medical Genetics DepartmentHospital General de México Dr. Eduardo LiceagaMexico CityMexico
- Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoMexico CityMexico
| | - Cesar Humberto Fregoso‐Ron
- Facultad de MedicinaUniversidad Nacional Autónoma de MéxicoMexico CityMexico
- Maternal Fetal Medicine DepartmentHospital General de México Dr. Eduardo LiceagaMexico CityMexico
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