Molecular genetic analyses of trinucleotide repeat expensions

Trinucleotide repeat expansions underlie several human genetic disorders, which show progressive severity over subsequent generations due to repeat length variation. We have identified the first case of a triplet expansion disorder in the model plant Arabidopsis that shares striking parallels with the human condition at the repeat level. This finding opens up possibilities of studying repeat length changes acrossgenerations due to the short generation time and the availability of genetic tools. Here we propose to use this simple plant model to study the variations in repeat lengths over several generations. This proposal will lead to the understanding of the molecular mechanisms that govern triplet expansions in subsequent generations.