If you’ve ever looked over at your siblings and wondered how the heck you’re even related to them, you’re not alone. Genetics is weird like that. Even when only born a couple of years apart, full on brothers and sisters sometimes seem like they were born on different planets. It happens.
One of the stranger aspects of genetics, according to a study out of the University of North Carolina Health Care, is that even though moms and dads contribute the exact same number of genes, most of us end up more like our dads than our moms.
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Even those of us who look more like our moms than our dads actually resemble our dads more at a genetic level, according to the study’s authors.
Yes, each parent contributes the same amount of genetic material to a child. However, it appears that the father’s contribution tends to play a more dominant role when it comes to genes expressing themselves.
“So imagine that a certain kind of mutation is bad. If inherited from the mother, the gene wouldn’t be expressed as much as it would be if it were inherited from the father,” researcher Pardo-Manuel de Villena explained to Science Daily . “So, the same bad mutation would have different consequences in disease if it were inherited from the mother or from the father.”
There are many examples of how a father’s genes can dominate.
One big one is whether a child is born male or female. The determining factor is whether a father’s contribution carries an X chromosome, which would make the child female, or a Y chromosome, making the child a male. But according to a Newcastle University study , checking out a dad’s family tree can provide some hints.
So, prospective dads out there, if you have many brothers, you’re more likely to have sons. If you have sisters, you’re more likely to have daughters, too.
Another thing dads pass along is, well, the likelihood of being able to conceive at all.
As a study published in the European Society of Human Reproduction and Embryology found, fertility issues may pass from father to son. It’s not 100% confirmed that that’s the case, but boys conceived via IVF are more likely to have low-quality swimmers compared to those conceived in families without sperm quality issues.
Kids tend to get their mental health from their fathers as well.
Specifically, fathers with schizophrenia, hyperactivity disorder, or attention deficit disorder are more likely to pass those along to their kids, according to a study published in JAMA Psychology .
What’s more, as men age, their sperm can gain more mutations, which can increase the risk of their children developing adverse mental health issues.
You probably have your dad’s smile, too.
Or at least similar dental bills. Things like tooth size and position, as well as jaw shape, tend to come from both parents, but as with so many other traits, the father’s genes can be expressed more dominantly.
Your height tends to come from your dad as well.
Research at Britain’s Royal Devon and Exeter Hospital showed that tall dads tended to have longer babies.
While ultimately how tall a child will grow to be will be determined by environmental factors as well, at least initially, height comes from the father, and those tall dads give their kids a leg up.
