The consequences of obesity to both the affected
individual and our society are becoming clearer and clearer every day. However,
no study to date has considered whether paternal obesity can directly affect
the health of their offspring. Perhaps, this is not surprising given that
research considering prenatal development has typically focused on mothers,
whose diet, smoking and experience of stressors affects the unborn baby during
its development. However, a new study has now gone a step further by suggesting
that epigenetic factors (such as being obese, experiencing stress etc.) may
affect the sperm of the father, which in turn could affect the offspring’s
health status.
The study, which is due to be published in BMC Medicine,
assessed a total of 79 infants and their parents. In order to do so, the
researchers took samples from the umbilical cord and examined the DNA from the
blood leukocytes. They also assessed parents using questionnaires, which were
compared to medical records. The key findings indicated that paternal obesity
was associated with DNA hypomethylation of the insulin growth factor (IGF2)
gene in offspring. Specifically, it was lower among children whose fathers were
obese than among children whose fathers were not obese. Although these findings are at risk of being
sensationalised, the researchers concluded that further studies are needed to
fully understand the implications of the study.
We find this study interesting, although it is clear this
field is still in its infancy. It is known that DNA methylation regulates some
genes and IGF2 has been linked to the risk of some cancers. However, in order
to establish that obese fathers’ spermatogenesis is affected by their obesity which
in turn affects DNA hypomethylation of the insulin growth factor (IGF2) gene in
offspring many more studies need to be done. These studies would need to
include other factors such paternal presence of diabetes or nutrition affecting
the outcome of the study. They would also need to include a larger sample size,
and more advanced statistical methods than several regressions.
We never cease to be surprised at
all the risks obesity brings with it, and feel that it would be unfortunate if
these findings were shown to be true. If these findings were substantiated,
then we would be keen to see whether these risks would be reversible with
paternal weight loss.