RT Journal Article
SR Electronic
T1 Hypermobile Ehlers-Danlos syndrome (hEDS) phenotype in fragile X premutation carriers: case series
JF Journal of Medical Genetics
JO J Med Genet
FD BMJ Publishing Group Ltd
SP jmedgenet-2020-107609
DO 10.1136/jmedgenet-2020-107609
A1 Nattaporn Tassanakijpanich
A1 Forrest J McKenzie
A1 Yingratana A McLennan
A1 Elisabeth Makhoul
A1 Flora Tassone
A1 Mittal J Jasoliya
A1 Christopher Romney
A1 Ignacio Cortina Petrasic
A1 Kaye Napalinga
A1 Caroline B Buchanan
A1 Paul Hagerman
A1 Randi Hagerman
A1 Emily L Casanova
YR 2021
UL http://jmg.bmj.com/content/early/2021/07/18/jmedgenet-2020-107609.abstract
AB Background While an association between full mutation CGG-repeat expansions of the Fragile X Mental Retardation 1 (FMR1) gene and connective tissue problems are clearly described, problems in fragile X premutation carriers (fXPCs) CGG-repeat range (55–200 repeats) of the FMR1 gene may be overlooked.Objective To report five FMR1 fXPCs cases with the hypermobile Ehlers-Danlos syndrome (hEDS) phenotype.Methods We collected medical histories and FMR1 molecular measures from five cases who presented with joint hypermobility and loose connective tissue and met inclusion criteria for hEDS.Results Five cases were female and ranged between 16 and 49 years. The range of CGG-repeat allele sizes ranged from 66 to 150 repeats. All had symptoms of hEDS since early childhood. Commonalities in molecular pathogenesis and coexisting conditions between the fXPCs and hEDS are also presented. The premutation can lead to a reduction of fragile X mental retardation protein, which is crucial in maintaining functions of the extracellular matrix-related proteins, particularly matrix metallopeptidase 9 and elastin. Moreover, elevated FMR1 messenger RNA causes sequestration of proteins, which results in RNA toxicity.Conclusion Both hEDS phenotype and premutation involvement may co-occur because of related commonalities in pathogenesis.