European combined analysis of the CTG18.1 and the ERDA1 CAG/CTG repeats in bipolar disorder.
Several groups have reported association between large CAG/CTG repeats in the genome and BP disorder using the Repeat Expansion Detection (RED) method. Molecular interpretation studies demonstrated that around 90% of the large CAG/CTG repeats detected by RED can by explained by repeat size at either the CTG18.1 or ERDA-1 locus. In this study we report the findings on a large European BP case-control sample analysed for these two frequently expanded repeats. The frequency of expanded alleles (>40 repeats) at the CTG18.1 locus was significantly higher in the subgroup of patients with a more severe phenotype BPI and a positive first degree family history than in a group of matched controls (9% vs 5%). No difference in ERDA-1 expansion frequency was seen between BP cases and matched controls. We conclude that the ERDA-1 locus is not related to the BP phenotype while expanded alleles at the CTG18.1 locus cannot be excluded as a vulnerability factor for BP disorder.
Del-Favero
Jurgen
J
Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp (UIA), Belgium.
Gestel
Sofie Van
SV
Børglum
Anders D
AD
Muir
Walter
W
Ewald
Henrik
H
Mors
Ole
O
Ivezic
Sladana
S
Oruc
Lilijana
L
Adolfsson
Rolf
R
Blackwood
Douglas
D
Kruse
Torben
T
Mendlewicz
Julien
J
Schalling
Martin
M
Van Broeckhoven
Christine
C
D000483:Alleles; D001714:Bipolar Disorder / Q000235:genetics*; D016022:Case-Control Studies; D005060:Europe; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*