GAA repeat instability in Friedreich ataxia YAC transgenic mice.
Friedreich ataxia (FRDA) is primarily caused by an unstable GAA repeat-expansion mutation within intron 1 of the FRDA gene. However, the exact mechanisms leading to this expansion and its consequences are not fully understood. To study the dynamics of this mutation, we have generated two lines of human FRDA YAC transgenic mice that contain GAA repeat expansions within the appropriate genomic context. We have detected intergenerational instability and age-related somatic instability in both lines, with pronounced expansions found in the cerebellum. The dynamic nature of our transgenic GAA repeats is comparable with previous FRDA patient somatic tissue data. However, there is a difference between our FRDA YAC transgenic mice and other trinucleotide-repeat mouse models, which do not show pronounced repeat instability in the cerebellum. This represents the first mouse model of FRDA GAA repeat instability that will help to dissect the mechanism of this repeat.
Al-Mahdawi
Sahar
S
Department of Medical Genetics, Division of Medicine, Imperial College London, North West Thames Regional Genetics Service, Northwick Park Hospital, Watford Road, Harrow, HA1 3UJ, UK.
Pinto
Ricardo Mouro
RM
Ruddle
Piers
P
Carroll
Christopher
C
Webster
Zoe
Z
Pook
Mark
M
D000375:Aging / Q000235:genetics; D000818:Animals; D002531:Cerebellum / Q000378:metabolism; D018244:Chromosomes, Artificial, Yeast / Q000235:genetics*; D004247:DNA / Q000235:genetics / Q000378:metabolism; D004195:Disease Models, Animal; D005621:Friedreich Ataxia / Q000235:genetics*; D042822:Genomic Instability / Q000235:genetics*; D033862:Iron-Binding Proteins / Q000235:genetics*; D051379:Mice; D008822:Mice, Transgenic; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*; D000096923:Frataxin
D004247:DNA; D033862:Iron-Binding Proteins; D000096923:Frataxin