EPIGENETICS AND CHANGING ANTS SIZE MARTIN ŠTEFKO

EPIGENETICS START Causal interactions between genes and their products which bring the phenotype into being (Waddington, 1942) change in phenotype without a change in genotype. Crossveinless produced by mutant alleles or simply by exposing pupae to heat shock. The capacity to respond to an external stimulus by some development reaction must itself be under genetic control Mutant alleles

DNA METHYLATION biochemical process controls the expression of certain genes like a dimmer can turn a light up or down

EXPERIMENT Investigation the developmental role of DNA methylation in generating continuous size variation of workers in an ant colony

WHY ANTS? : species Camponotus floridanus (better known as the Florida carpenter ant). 1 Little genetic difference between workers in colony 2 Mapped genome

STEP BY STEP identifying a key gene for each trait and how it is affected epigenetically (by the environment), influence the degree of its expression by methylation of this gene creating variation in how specific traits (height) are expressed

RESULTS More methylated EGFR gene Larger ant

QUOTES „It’s a discovery that completely changes our understanding of how human variation comes to be,” says Abouheif. „If, as we believe, this epigenetic mechanism applies to a key gene in each area, the change is so enormous that it’s hard to even imagine right now how it will influence research in everything from health to cognitive development to farming“

ARTICLE Epigenetic variation in the ​ Egfr gene generates quantitative variation in a complex trait in ants: Sebastian Alvarado, Rajendhran Rajakumar, Ehab Abouheif & Moshe Szyf, Nature Communications 6, Article number: 6513, 11 March 2015