Melbourne: New research involving Monash University biologists has debunked the
view that males just pass on genetic material and not much else to their
offspring. Instead, it found a father’s diet can affect their son’s
ability to out-compete a rival's sperm after mating. The study
sought to understand if the nutritional history of fathers had an effect
on their sons. Experiments were carried out in the fruit fly, which
shares many similar pathways and characteristics with human genes. One
of the lead authors of the study, Dr Susanne Zajitschek from the School
of Biological Sciences, said the study highlighted the importance of
the paternal environment on future generations, even a long time before
offspring were produced.
“Our study found that males that were
raised on either high or low protein diets, but spent their adulthood on
an intermediate diet, produced sons that had large differences in gene
expression, which most likely contributed to the resulting differences
in sperm competitiveness,” Dr Zajitschek said.
“They differed in
their ability to sire offspring, with the high-protein dads producing
sons who were doing much better in sperm competition, which means their
sperm was more likely to win against a competitor’s sperm within the
female tract.
“We also found that the immune response genes were
less active in sons of low-protein fathers, while metabolic and
reproductive processes were increased in sons of fathers on a high
protein diet,” she said.
The research, published in Biology Letters, is
one of only a few studies to have so far reported trans-generational
effects in relation to diet quality, and one of the first to report on
the post-copulatory advantages conferred by parental diet.
Researchers
from Monash University, George Washington University, and the
Spanish-based Donana Biological Station took part in the study which
examined how high- and low-protein paternal larval diet influenced
post-copulatory sexual selection and gene expression in the sons of
fruit flies (Drosophila melanogaster).