{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T22:41:47Z","timestamp":1770417707970,"version":"3.49.0"},"reference-count":24,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2019,9,27]],"date-time":"2019-09-27T00:00:00Z","timestamp":1569542400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>Two probands are reported with pathogenic and likely pathogenic COL5A1 variants (frameshift and splice site) in whom no collagen flowers have been identified with transmission electron microscopy (TEM). One proband fulfils the clinical criteria for classical Ehlers-Danlos syndrome (cEDS) while the other does not and presents with a vascular complication. This case report highlights the significant intrafamilial variability within the cEDS phenotype and demonstrates that patients with pathogenic COL5A1 variants can have an absence of collagen flowers on TEM skin biopsy analysis. This has not been previously reported in the literature and is important when evaluating the significance of a TEM result in patients with clinically suspected cEDS and underscores the relevance of molecular analysis.<\/jats:p>","DOI":"10.3390\/genes10100762","type":"journal-article","created":{"date-parts":[[2019,9,27]],"date-time":"2019-09-27T11:14:35Z","timestamp":1569582875000},"page":"762","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":14,"title":["Absence of Collagen Flowers on Electron Microscopy and Identification of (Likely) Pathogenic COL5A1 Variants in Two Patients"],"prefix":"10.3390","volume":"10","author":[{"given":"Chloe","family":"Angwin","sequence":"first","affiliation":[{"name":"National Complex Ehlers-Danlos Syndrome Service London, North West Health Care NHS Trust, Harrow HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Angela F.","family":"Brady","sequence":"additional","affiliation":[{"name":"National Complex Ehlers-Danlos Syndrome Service London, North West Health Care NHS Trust, Harrow HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3105-5990","authenticated-orcid":false,"given":"Marina","family":"Colombi","sequence":"additional","affiliation":[{"name":"Division of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5045-819X","authenticated-orcid":false,"given":"David J. P.","family":"Ferguson","sequence":"additional","affiliation":[{"name":"Nuffield Department of Clinical Laboratory Sciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK"},{"name":"Department Biological &amp; Medical Sciences, Oxford Brookes University, Oxford OX3 0BP, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rebecca","family":"Pollitt","sequence":"additional","affiliation":[{"name":"Connective Tissue Disorders Service, Sheffield Diagnostic Genetics Service, Sheffield S10 2TQ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"F. Michael","family":"Pope","sequence":"additional","affiliation":[{"name":"Department of Dermatology, Chelsea and Westminster Hospital, London, SW10 9NH UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7025-2495","authenticated-orcid":false,"given":"Marco","family":"Ritelli","sequence":"additional","affiliation":[{"name":"Division of Biology and Genetics, Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sofie","family":"Symoens","sequence":"additional","affiliation":[{"name":"Center for Medical Genetics, Ghent University Hospital, B-9000 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2847-1376","authenticated-orcid":false,"given":"Neeti","family":"Ghali","sequence":"additional","affiliation":[{"name":"National Complex Ehlers-Danlos Syndrome Service London, North West Health Care NHS Trust, Harrow HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fleur S.","family":"van Dijk","sequence":"additional","affiliation":[{"name":"National Complex Ehlers-Danlos Syndrome Service London, North West Health Care NHS Trust, Harrow HA1 3UJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1002\/ajmg.c.31552","article-title":"The 2017 international classification of the Ehlers\u2013Danlos syndromes","volume":"175","author":"Malfait","year":"2017","journal-title":"Am. 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