Assessing the impact of transgenerational epigenetic variation on complex traits.
Loss or gain of DNA methylation can affect gene expression and is sometimes transmitted across generations. Such epigenetic alterations are thus a possible source of heritable phenotypic variation in the absence of DNA sequence change. However, attempts to assess the prevalence of stable epigenetic variation in natural and experimental populations and to quantify its impact on complex traits have been hampered by the confounding effects of DNA sequence polymorphisms. To overcome this problem as much as possible, two parents with little DNA sequence differences, but contrasting DNA methylation profiles, were used to derive a panel of epigenetic Recombinant Inbred Lines (epiRILs) in the reference plant Arabidopsis thaliana. The epiRILs showed variation and high heritability for flowering time and plant height ( approximately 30%), as well as stable inheritance of multiple parental DNA methylation variants (epialleles) over at least eight generations. These findings provide a first rationale to identify epiallelic variants that contribute to heritable variation in complex traits using linkage or association studies. More generally, the demonstration that numerous epialleles across the genome can be stable over many generations in the absence of selection or extensive DNA sequence variation highlights the need to integrate epigenetic information into population genetics studies.
Johannes
Frank
F
Unité de Recherche en Génomique Végétale, Centre National de la Recherche Scientifique (CNRS) UMR 8114, Institut National de la Recherche Agronomique (INRA) UMR 1165, Université d'Evry Val d'Essonne, Evry, France.
Porcher
Emmanuelle
E
Teixeira
Felipe K
FK
Saliba-Colombani
Vera
V
Simon
Matthieu
M
Agier
Nicolas
N
Bulski
Agnès
A
Albuisson
Juliette
J
Heredia
Fabiana
F
Audigier
Pascal
P
Bouchez
David
D
Dillmann
Christine
C
Guerche
Philippe
P
Hospital
Frédéric
F
Colot
Vincent
V
D017360:Arabidopsis / Q000235:genetics*; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D014644:Genetic Variation; D019655:Quantitative Trait, Heritable