{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T02:01:04Z","timestamp":1760234464991,"version":"build-2065373602"},"reference-count":29,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,5,24]],"date-time":"2021-05-24T00:00:00Z","timestamp":1621814400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000925","name":"National Health and Medical Research Council","doi-asserted-by":"publisher","award":["1049299 and 1103389"],"award-info":[{"award-number":["1049299 and 1103389"]}],"id":[{"id":"10.13039\/501100000925","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100005381","name":"Financial Markets Foundation for Children","doi-asserted-by":"publisher","award":["2017 \u2013 361"],"award-info":[{"award-number":["2017 \u2013 361"]}],"id":[{"id":"10.13039\/501100005381","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Medical Research Future Fund","award":["MRF1141334"],"award-info":[{"award-number":["MRF1141334"]}]},{"name":"Victorian Government\u2019s Operational Infrastructure Support Program","award":["no grant number"],"award-info":[{"award-number":["no grant number"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Genes"],"abstract":"<jats:p>We describe a female with a 72 CGG FMR1 premutation (PM) (CGG 55\u2013199) and family history of fragile X syndrome (FXS), referred for prenatal testing. The proband had a high risk of having an affected pregnancy with a full mutation allele (FM) (CGG &gt; 200), that causes FXS through hypermethylation of the FMR1 promoter. The CGG sizing analysis in this study used AmplideX triplet repeat primed polymerase chain reaction (TP-PCR) and long-range methylation sensitive PCR (mPCR). These methods detected a 73 CGG PM allele in the proband\u2019s blood, and a 164 CGG PM allele in her male cultured chorionic villus sample (CVS). In contrast, the Southern blot analysis showed mosaicism for: (i) a PM (71 CGG) and an FM (285\u2013768 CGG) in the proband\u2019s blood, and (ii) a PM (165 CGG) and an FM (408\u2013625 CGG) in the male CVS. The FMR1 methylation analysis, using an EpiTYPER system in the proband, showed levels in the range observed for mosaic Turner syndrome. This was confirmed by molecular and cytogenetic karyotyping, identifying 45,X0\/46,XX\/47,XXX lines. In conclusion, this case highlights the importance of Southern blot in pre- and postnatal testing for presence of an FM, which was not detected using AmplideX TP-PCR or mPCR in the proband and her CVS.<\/jats:p>","DOI":"10.3390\/genes12060798","type":"journal-article","created":{"date-parts":[[2021,5,24]],"date-time":"2021-05-24T12:38:01Z","timestamp":1621859881000},"page":"798","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Detection of Cryptic Fragile X Full Mutation Alleles by Southern Blot in a Female and Her Foetal DNA via Chorionic Villus Sampling, Complicated by Mosaicism for 45,X0\/46,XX\/47,XXX"],"prefix":"10.3390","volume":"12","author":[{"given":"Alison","family":"Pandelache","sequence":"first","affiliation":[{"name":"Victorian Clinical Genetics Services, Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, VIC 3052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Francis","sequence":"additional","affiliation":[{"name":"Victorian Clinical Genetics Services, Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, VIC 3052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ralph","family":"Oertel","sequence":"additional","affiliation":[{"name":"Victorian Clinical Genetics Services, Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, VIC 3052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rebecca","family":"Dickson","sequence":"additional","affiliation":[{"name":"Maternal Fetal Medicine Department, Royal Hospital for Women, Randwick, NSW 2031, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rani","family":"Sachdev","sequence":"additional","affiliation":[{"name":"Centre for Clinical Genetics, Sydney Children\u2019s Hospital, Randwick, NSW 2031, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ling","family":"Ling","sequence":"additional","affiliation":[{"name":"Diagnosis and Development, Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, VIC 3052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dinusha","family":"Gamage","sequence":"additional","affiliation":[{"name":"Diagnosis and Development, Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, VIC 3052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6405-269X","authenticated-orcid":false,"given":"David E.","family":"Godler","sequence":"additional","affiliation":[{"name":"Diagnosis and Development, Murdoch Children\u2019s Research Institute, Royal Children\u2019s Hospital, Melbourne, VIC 3052, Australia"},{"name":"Faculty of Medicine, Dentistry and Health Sciences, Department of Paediatrics, University of Melbourne, Parkville, VIC 3052, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1648","DOI":"10.1002\/ajmg.a.36511","article-title":"Epidemiology of fragile X syndrome: A systematic review and meta-analysis","volume":"164A","author":"Hunter","year":"2014","journal-title":"Am. 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A"}],"container-title":["Genes"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4425\/12\/6\/798\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:06:51Z","timestamp":1760162811000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4425\/12\/6\/798"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,5,24]]},"references-count":29,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["genes12060798"],"URL":"https:\/\/doi.org\/10.3390\/genes12060798","relation":{},"ISSN":["2073-4425"],"issn-type":[{"type":"electronic","value":"2073-4425"}],"subject":[],"published":{"date-parts":[[2021,5,24]]}}}