Incidence of Fragile X syndrome in Ireland.
Described as the commonest single gene cause of learning disability internationally, the incidence of Fragile X syndrome (FXS) has never previously been determined in Ireland. The aim of this work was to determine the observed incidence of FXS in the island of Ireland; the Republic of Ireland (ROI) and Northern Ireland (NI) separately and combined. Ascertainment was achieved for a cross-sectional study by a retrospective, clinical and laboratory database review of positive FXS cases, born in either ROI or NI, between years 2000-2009 inclusive. The observed incidence of FXS per 10,000 live births in the island of Ireland in males was 0.94 (95%CI: 0.75-1.13) or ∼1:10,600 and in females was 0.23 (95%CI: 0.14-0.32) or ∼1:43,000. Comparable testing rates for FXS are present in ROI and NI, with on average 1.48% (1.30% in ROI, 1.96% in NI) of live male births and 0.4% (0.35% in ROI, 0.55% in NI) of live female births undergoing analysis which is comparable to other centres internationally. This study demonstrates the observed incidence of FXS in the island of Ireland is (i) approximately half the estimated worldwide incidence in males and is not explained by low levels of testing, and (ii) approximately one quarter the estimated worldwide incidence in females which may be explained by low levels of testing. © 2017 Wiley Periodicals, Inc.
Department of Clinical Genetics, Our Lady's Children's Hospital Crumlin, Crumlin, Dublin, Ireland.
James J
JJ
O'Byrne
Department of Clinical Genetics, Our Lady's Children's Hospital Crumlin, Crumlin, Dublin, Ireland.
Michael
M
Sweeney
Northern Ireland Regional Genetics Centre, Belfast Health and Social Care Trust/City Hospital, Belfast, Northern Ireland.
Deirdre E
DE
Donnelly
National Rare Diseases Office, Mater Misericordiae Hospital, Dublin, Ireland.
Deborah M
DM
Lambert
Northern Ireland Regional Genetics Centre, Belfast Health and Social Care Trust/City Hospital, Belfast, Northern Ireland.
Eleanor D
ED
Beattie
Northern Ireland Regional Genetics Centre, Belfast Health and Social Care Trust/City Hospital, Belfast, Northern Ireland.
Celine M
CM
Gervin
Department of Clinical Genetics and University College Dublin School of Medicine and Medical Sciences, Our Lady's Children's Hospital Crumlin, Crumlin, Dublin, Ireland.
David E
DE
Barton
National Rare Diseases Office, Mater Misericordiae Hospital, Dublin, Ireland.|Academic Centre on Rare Diseases, University College Dublin School of Medicine and Medical Sciences, Belfield, Dublin, Ireland.
Sally A
SA
Lynch
D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D005600:Fragile X Syndrome / Q000175:diagnosis / Q000453:epidemiology* / Q000235:genetics; D005820:Genetic Testing; D006801:Humans; D015994:Incidence; D007223:Infant; D007494:Ireland / Q000453:epidemiology; D008297:Male; D009154:Mutation; D009660:Northern Ireland / Q000453:epidemiology; D010641:Phenotype; D011159:Population Surveillance; D012189:Retrospective Studies
Fragile X syndrome; Ireland; epidemiology; incidence