Everyone is a mutant but some are prone to diverge more than others, report scientists at University of Utah Health.
At birth, children typically have 70 new genetic mutations compared to their parents (out of the 6 billion letters that make both parental copies of DNA sequence). A new study published in eLife shows that number varies dramatically with some people being born with twice as many mutations as others, and that characteristic runs in families.
That difference is based largely on two influences. One is the age of a child’s parents. A child born to a father who is 35 years old will likely have more mutations than a sibling born to the same father at 25.
“The number of mutations we pass on to the next generation increases with parental age,” said Thomas Sasani, lead author of the study and a graduate student in human genetics at U of U Health. Previous studies have demonstrated the phenomenon, also confirmed by this study.
Another difference is that the effects of parental age on mutation rates differ considerably among families — much more than had been previously appreciated. In one family, a child may have two additional mutations compared to a sibling born when their parents were ten years younger. Two siblings born ten years apart to a different set of parents may vary by more than 30 mutations.
PHOTO CREDIT: Charlie Ehlert/University of Utah Health
Aaron Quinlan
“This shows that we as parents are not all equal in this regard,” said Aaron Quinlan, senior author of the study. He is also a professor of human genetics at U of U Health and associate director of the Utah Center for Genetic Discovery. “Some of us pass on more mutations than others and this is an important source of genetic novelty and genetic disease.”
Impacts of new mutations depend on where they land in our DNA, and on the passage of time. On occasion the genetic changes cause serious disease, but the majority occur in parts of our genetic code that don’t have obvious effects on human health.
And even though new changes make up a small fraction of the overall DNA sequence, they add up with each subsequent generation. Increasing the so-called mutation load could potentially make individuals more susceptible to illness, said Sasani. It remains to be determined whether factors that impact the mutation rate increase the likelihood for certain diseases.
Although the majority of new mutations originally arise in fathers’ sperm, not all do. One in five mutations come from mothers’ eggs, and increasing age does not drive as many new mutations in moms as it does in dads. Further, it’s estimated that one in ten new mutations seen in children come from neither parent. Instead, they arise anew in the embryo soon after fertilization.
The new insights were found by performing whole genome sequencing and genetic analysis on 603 individuals from 33 three-generation families from Utah, the largest study of its kind. The families were part of the Centre d’Etude du Polymorphisme Humain (CEPH) consortium that were central to many key investigations that formed a modern understanding of human genetics. The large size of the Utah CEPH families, which had as many as 16 children over a span of 27 years, made them well-suited for this new investigation.
It’s surprising that the Utah CEPH families have a large range in the number of mutations they accumulate, said Quinlan. That’s because the families are similar in many ways. They are all of European ancestry, live within the same geographic region, and likely have similar lifestyles and environmental exposures.
“We don’t know what’s driving the variability,” Quinlan continued, but reasoned that it stems from a combination of genetics, environment, and exposure to mutagens. Given that these influences differ widely across the globe, he hypothesized that “variability in mutation rates worldwide must be much, much larger.”
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In addition to Sasani and Quinlan, co-authors were Brent Pedersen and Lynn B. Jorde from U of U Health, Ziyue Gao from Stanford University and Lisa Baird and Molly Przeworski from Columbia University. The research was supported by the National Institutes of Health and published as “Large, three-generation human families reveal post-zygotic mosaicism and variability in germline mutation accumulation”.
FAQs
Everyone is a mutant but some are prone to diverge more than others, report scientists at University of Utah Health. At birth, children typically have 70 new genetic mutations compared to their parents (out of the 6 billion letters that make both parental copies of DNA sequence).
How many mutations does each person have? ›
This means that a human genome accumulates around 64 new mutations per generation because each full generation involves a number of cell divisions to generate gametes.
Does everyone have genetic mutations? ›
One in five 'healthy' adults may carry disease-related genetic mutations.
Are mutants among us? ›
Ladies and gentlemen, the truth is that mutants are very real, and they are among us. We have people that live among us today on planet Earth that are happy to display themselves as if they were mutants from another planet.
Do we have mutants in real life? ›
Scientists estimate that every time the human genome replicates itself there are roughly 100 new mutations. Most of them are benign and negligible, but every so often a mutation expresses itself in the form of a seemingly superhuman ability.
Can non humans be mutants? ›
The nature of the Multiverse making virtually everything possible create the possibility of amounts of non-humans mutants such as the few "Xaviers" shown. Namor in the Earth-199999, is a mutant Talokanil.
Do humans have a high mutation rate? ›
Nevertheless, despite the high per-generation rate in humans, on a per–cell division basis, the human germline mutation rate is lower than that in any other organism for which reliable data are available.
Do humans have variants? ›
State-of-the art tools perfected during the 2000s led to the discovery of the tremendous variation in the human genome. Knowledge gained from this work included learning that the genomes of two human individuals are 99.5% identical at the DNA level, yet every person has variants that make them unique.
What are the best mutations in humans? ›
Examples of beneficial mutations include HIV resistance, lactose tolerance, and trichromatic vision.
Do we all have genetic defects? ›
Around 65% of people have some kind of health problem as a result of congenital genetic mutations. Due to the significantly large number of genetic disorders, approximately 1 in 21 people are affected by a genetic disorder classified as "rare" (usually defined as affecting less than 1 in 2,000 people).
KAT6A syndrome is an extremely rare genetic neurodevelopmental disorder in which there is a variation (mutation) in the KAT6A gene. Variations in the KAT6A gene can potentially cause a wide variety of signs and symptoms; how the disorder affects one child can be very different from how it affects another.
Can a man's genes alter yours? ›
your genetics don't get altered by anyone you have sex with. The only genetic material that is changed is the father's half of the genetics of any resulting embryos. Your egg has half of what's needed, his sperm provides the other half. Your genetics are unchanged, just those of any resulting pregnancy.
Do all humans have mutant genes? ›
“Mutants are actually extremely common,” says OMRF scientist Dr. Chris Sansam. “Someone without any mutations would be the real anomaly.” Mutations are changes to a person's genetic code, and they can come about from exposure to an external environmental factor, such as cigarette smoke or radiation.
How many mutants are left? ›
While it has been stated that there are at least 198 remaining mutants, according to Henry Peter Gyrich in Avengers: The Initiative, there are actually "around 300"; the 198 number is merely the number of mutants the US government has cataloged, with a 199th mutant (Mutant Zero) being off the record.
Why are there no more mutants? ›
The Decimation reduced the mutant population down to a few hundred, as most mutants were depowered and some others were killed as a result of losing their powers. In total, 986,618 mutants were either depowered or killed by the Decimation.
What's the difference between mutants and humans? ›
Unsourced material may be challenged and removed. In American comic books published by Marvel Comics, a mutant is a human being that possesses a genetic trait called the X-gene. It causes the mutant to develop superhuman powers that manifest at puberty.
Are there any human mutations? ›
Symptoms of genetic conditions depend on which gene has a mutation. There are many different diseases and conditions caused by mutations. The signs and symptoms you experience could include: Physical characteristics like facial abnormalities, a cleft palate, webbed fingers and toes, or short stature.
Is there such thing as a mutant? ›
In biology, and especially in genetics, a mutant is an organism or a new genetic character arising or resulting from an instance of mutation, which is generally an alteration of the DNA sequence of the genome or chromosome of an organism. It is a characteristic that would not be observed naturally in a specimen.
Are mutants born or created? ›
For some mutants, several years of self-discipline are needed before they can control their powers, while others never gain full control of their powers. Mutants may be born to human or mutant parents, though the odds of a mutant birth are much better for the latter.
