RT Journal Article
T1 Molecular testing for fragile X: analysis of 5062 tests from 1105 fragile X families--performed in 12 clinical laboratories in Spain.
A1 Tejada, María-Isabel
A1 Glover, Guillermo
A1 Martínez, Francisco
A1 Guitart, Miriam
A1 Diego-Otero, Yolanda de
A1 Fernández-Carvajal, Isabel
A1 Ramos, Feliciano J
A1 Hernández-Chico, Concepción
A1 Pintado, Elizabet
A1 Rosell, Jordi
A1 Calvo, María-Teresa
A1 Ayuso, Carmen
A1 Ramos-Arroyo, María-Antonia
A1 Maortua, Hiart
A1 Milà, Montserrat
K1 Alelos
K1 Síndrome del cromosoma X frágil
K1 Frecuencia génica
K1 Pruebas genéticas
K1 Sistema de registros
K1 España
AB Fragile X syndrome is the most common inherited form of intellectual disability. Here we report on a study based on a collaborative registry, involving 12 Spanish centres, of molecular diagnostic tests in 1105 fragile X families comprising 5062 individuals, of whom, 1655 carried a full mutation or were mosaic, three cases had deletions, 1840 had a premutation, and 102 had intermediate alleles. Two patients with the full mutation also had Klinefelter syndrome. We have used this registry to assess the risk of expansion from parents to children. From mothers with premutation, the overall rate of allele expansion to full mutation is 52.5%, and we found that this rate is higher for male than female offspring (63.6% versus 45.6%; P < 0.001). Furthermore, in mothers with intermediate alleles (45-54 repeats), there were 10 cases of expansion to a premutation allele, and for the smallest premutation alleles (55-59 repeats), there was a 6.4% risk of expansion to a full mutation, with 56 repeats being the smallest allele that expanded to a full mutation allele in a single meiosis. Hence, in our series the risk for alleles of <59 repeats is somewhat higher than in other published series. These findings are important for genetic counselling.
PB Hindawi Publishing Corporation
YR 2014
FD 2014-05-28
LK http://hdl.handle.net/10668/1836
UL http://hdl.handle.net/10668/1836
LA en
NO Tejada MI, Glover G, Martínez F, Guitart M, de Diego-Otero Y, Fernández-Carvajal I, et al. Molecular testing for fragile X: analysis of 5062 tests from 1105 fragile X families--performed in 12 clinical laboratories in Spain. Biomed Res Int; 2014:195793
NO Journal Article; Multicenter Study;
DS RISalud
RD Apr 9, 2025