Discolored skin, atypically long body parts, and secret diseases leading to revolution:
the consequences of historical inbreeding are dramatic and hard to ignore.
According to a 2010 study published in the Journal of the American Medical Association,
CT scans of Tutankhamun's mummy revealed quite a bit about the young king, who died at the
age of 19. First, there was a broken leg and an active case of malaria, which may have been the
immediate issues contributing to his death. He was also managing scoliosis and a cleft palate while
simultaneously suffering from a clubbed foot that would've made walking difficult. This was further
exacerbated by a degenerative disease that was eating away at the bones in his left foot.
It's hard to say for sure if King Tut's issues were all linked to his familial mating. However,
the study did confirm that he was almost certainly a product of royal inbreeding.
The pharaoh believed to be his father, Akhenaten,
did marry one of his sisters. Tut was also married to his own sister, or half-sister,
perhaps explaining why he had no heir and was buried with two miscarried fetuses.
The royals of ancient Ireland weren't exactly keen on sharing their wealth with outsiders. At least,
that seems to be the only explanation for the genetics of one man who was
buried in the Newgrange tomb built in Neolithic Ireland. According to a 2020 paper published
in Nature, he was found in an especially well-appointed section of the stone tomb,
which is believed to have been set aside for the elites of the era.
Researchers discovered that this man's particular genetic code indicated that he must've been
produced via first-degree incest. Specifically, he was almost certainly the product of a sibling or
parent-child union. Researchers also determined that he was related to others buried nearby.
Though there isn't much of a written record to back up this claim,
the DNA is hard to ignore. So too is the circumstantial evidence that indicates
that only the upper echelons of Stone Age Irish society were engaging in this
practice. Poor farmers weren't being laid to rest in an elaborate tomb, after all.
"It actually upgrades our DNA, believe it or not, by being on this land."
For the Fundamentalist Church of Jesus Christ of Latter-Day Saints, the drive to remain
within their highly conservative religious group is paired with the directive to have
as many children as possible within polygamous marriages. But the FLDS community of Short Creek
on the border between Utah and Arizona has begun to see the effects of generations of inbreeding.
The problem was first identified by pediatric neurologist Theodore Tarby,
who examined a young boy from the community in 1990. The child had unusual facial features and
significant developmental delays. Tarby determined that the boy had a rare genetic disorder known
as fumarase deficiency, which kneecaps the body's ability to supply energy and dramatically impairs
brain development. Affected people have cognitive impairments, seizures, and physical disabilities.
Fumarase deficiency was so rare that just a handful of cases were known at
the time. But doctors eventually found a staggering eight new cases in the Short
Creek FLDS community. Clearly, this was more than just a case of random genetic mutation.
When it comes to inbred royals, Charles II of Spain is the unfortunate poster child. It wasn't
exactly his fault that he was a member of the Habsburg dynasty. By the time he was born in 1661,
they were already notoriously inbred because they couldn't bear to dilute
their wealth and power via marriage with outsiders. It was all so tangled that
Charles' parents were niece and uncle, while his grandmother was also his aunt.
Charles was beset by a staggering range of problems,
from physical deformities to developmental delays, epilepsy,
and even early-onset baldness. After his death at the age of 38, doctors performed an autopsy
and wrote that he had a heart that was about as small as a peppercorn. Plus,
there were also his badly damaged internal organs and a single, blackened testicle.
"Yikes. Well, good luck with all that."
Perhaps most damaging to Charles and the entire Habsburg clan was
the fact that he couldn't produce an heir. He married twice but never
managed to have a child. Perhaps that was ultimately for the best,
as his failure to carry on the line spelled the end of the highly inbred dynasty in Spain.
Charles II may be the more famous case, but the title of Most Inbred Royal more rightfully
belongs to his niece, Maria Antonia of Austria. According to an analysis in the journal Heredity,
she had the highest known inbreeding coefficient in the whole family. It even exceeded the
inbreeding coefficient of someone born to a parent-child union or to full siblings. Her
father, Holy Roman Emperor Leopold I, and her mother, Margaret Theresa, were first cousins,
as well as uncle and niece to each other. Margaret Theresa was seriously inbred herself, and it's
been speculated that she died young in childbirth because of a genetically weakened system.
Perhaps that's also why Maria Antonia was the couple's only surviving child,
though the lack of reliable postpartum and pediatric care in the 17th century certainly
didn't help. Yet Maria Antonia seemed relatively unaffected by her mixed-up genetic legacy.
She was once slated to marry her uncle Charles II. But the marriage was reportedly
nixed because he was 12, she was 6, and the family needed heirs more quickly than
a couple of kids could manage. It likely didn't help that Charles may have already
obviously been affected by his own inbreeding. So instead, Maria Antonia married Maximilian II,
ruler of Bavaria. They had a few kids, but none of them made it past childhood. Maria Antonia
herself died of birth complications in December 1692 at the age of 23.
In the early days of Hawaiian culture, almost everyone was subject to an intense hierarchical
way of life. A select few called the ali'i sat at the top of the social pyramid and could be
divided into even smaller ranked categories. A complicated set of social rules, known as kapu,
demanded such respect for the ali'i that the highest-ranking chiefs would expect
most people to fling themselves face-down in their presence. Breaking kapu could spell death,
though the system was abolished by royals in the early 19th century.
Before that change, the ali'i were seriously restricted when it came to selecting spouses. The
solution was to marry first-degree relatives. The practice was once revered and considered a mark of
the highest status, with children produced from these unions considered especially high-ranking.
But Europeans who settled in the islands were downright horrified by the practice.
By the 1820s, King Kamehameha III and his sister Nahienaena were caught in an
emotionally fraught middle ground. They reportedly attempted to wed,
but Nahienaena was caught between the old ways and the new Christianity brought by missionaries,
and she was later persuaded to marry someone else. However,
she reportedly still had a child fathered by her brother, though the boy died shortly after birth.
Queen Victoria of England seemed generally healthy,
but her descendants weren't quite so lucky. She carried the gene for hemophilia,
a recessive disorder in which blood doesn't clot properly and can lead to
bleeding to death. Victoria's son Leopold died of hemophilia at just 30 years old.
"In the absence of effective treatment at the time,
very few children with hemophilia would've survived into adolescence."
Though Leopold was the first of Victoria's descendants known to have hemophilia,
he was definitely not the last, thanks to the limited gene pool of European royals. Victoria's
granddaughter Victoria Eugenie brought the gene to Spain, while three grandsons died of the
disease. Victoria's other granddaughter Alexandra carried it all the way to Russia and her only son,
Crown Prince Alexei. That offered an opening for the mystic Rasputin to work his way into
the graces of the imperial family after he supposedly helped Alexei.
Because the royals kept Alexei's condition under wraps, few understood why Rasputin
appeared to have so much sway over Alexandra and her family. This reportedly led to more
destabilization to the point that Rasputin was killed, the imperial family was assassinated,
and Russia became a communist country. The inbreeding of course wasn't solely
to blame for this turn of events, but it certainly played a part.
Tragically, some of the worst cases of inbreeding have occurred in deeply abusive environments,
like the Colt family of Australia. "Colt" is actually a court-provided pseudonym meant to
protect the minors who were caught up in the abuse. In 2012, a dozen children were
removed from the family's rural compound near Boorowa, New South Wales. Adults at
the compound were accused of severely neglecting the children's education, hygiene, and nutrition.
Further investigation revealed that multiple children had learning disabilities and one
reportedly had unusual facial features. It soon emerged that some had been sexually
abused by members of their own family, and that some were products of that abuse.
It all began when members of the family with the pseudonyms of "Timothy" and "June" moved
to Australia from New Zealand in the 1960s. Court statements indicate that June was the
daughter of a brother-sister pair. After June married Tim Colt, they moved to Australia and
had seven children. Over the years, Tim abused his own children and grandchildren,
as did other family members. Colt family members still suffer from the genetic effects
of inbreeding and years of social isolation that made joining wider society all the more difficult.
The German House of Wittelsbach was yet another European dynasty with a
rather inbred family tree. Most dramatic was arguably Ludwig II,
who ruled Bavaria from 1864 to 1886. He was generally uninterested in government,
as he instead spent money on extravagant building projects. His most famous is the
Neuschwanstein Castle, which is based on his love of fairy tales and revisionist history.
This castle and other building projects were seen as a symptom
of Ludwig's tenuous grip on reality. By the 1880s, he'd become something of a recluse,
and on June 10, 1886, he was declared insane and unfit to rule. Just three days later,
he died by drowning in a lake near one of his elaborate homes. The official verdict
was that it was suicide, while some believed that it was an accident, or even murder.
"Murder, murder, murder."
Born in 1793, Ferdinand I, Emperor of Austria, was the son of Holy Roman Emperor
Francis II and Maria Theresa of Naples and Sicily. His parents also happened
to be double first cousins, meaning that they had all four grandparents in common.
That marriage may explain why Ferdinand suffered from hydrocephalus speech difficulty, and seizures
throughout his life. Some accounts also claim that he had a cognitive disability. The hydrocephalus,
or high levels of fluid around the brain, also gave him a strikingly large head.
"While we're on it, how is your head?"
Ferdinand was also said to have had a seizure in the middle of his 1831
wedding to his distant cousin Maria Anna of Savoy. They never had children,
but at least Ferdinand was a relatively popular emperor until political unrest
pushed him to abdicate in December 1848. If his genes were the cause of his purported troubles,
they didn't affect his lifespan too terribly, as he died in 1875 at the age of 82.
Sometime around 1820, Martin Fugate moved from France to Kentucky. Then he married Elizabeth
Smith and they had seven children together, four of whom had blue skin. Both parents carried
a recessive gene for methemoglobinemia, a blood disorder characterized by abnormally high levels
of methemoglobin. The result, at least for some, is cyanosis that leads to strikingly blue skin.
Because the Fugates lived in a rural area at a time when long-distance travel was difficult,
their descendants had a limited pool of potential spouses. Martin and Elizabeth's
son reportedly married his own aunt, for instance. Eventually, the family produced
enough blue-skinned members that they became known locally as the Blue Fugates.
But as travel became easier, more of them married out of the group and reduced the
rates of methemoglobinemia in the family. With modern medical care,
anyone still exhibiting the blue skin can see it fade away within minutes after consuming a tablet
of methylene blue. This treatment turns their defective methemoglobin back into hemoglobin.
Egypt's queen Cleopatra VII was legendarily beautiful, but she and
her family may have also been seriously inbred. Her ancestors in the Greek Ptolemaic dynasty,
which ruled Egypt from 305 to 30 B.C., were very invested in keeping it in the family. Her
great-great-grandparents comprised only six people, as opposed to 16 in standard cases.
Cleopatra herself married her brother Ptolemy XIII and, later, another sibling,
Ptolemy XIV. This inbreeding may have contributed to the Ptolemaic obesity,
which some researchers have suggested may be due to inherited thyroid issues.
However, it's important to note that the ancient genealogies are hard to pin down
exactly. What's more, Cleopatra didn't seem obviously affected by her family's inbreeding,
as she ruled for 21 years before her death by suicide at age 39.
She also had four known children, but none with her family members.
"You are now dismissed."
Incan rulers were said to have begun marrying sisters or half-sisters in
an attempt to consolidate power and also tamp down the violent scheming that went
into pushing one candidate forward over another. And there's genetic evidence
that intermarriage occurred among the ancient people of the region.
At a 2017 conference, Sara K. Becker of the University of California, Riverside presented
the results of an excavation at a Peruvian burial site covering the years A.D. 500 to
1100. Excavators found 14 individuals with an unusual spinal condition that included an
extra lumbar vertebrae fused to the sacrum. The rarity of the condition, along with the
fact that so many people in one spot had it, indicated a significant level of inbreeding.
Another excavation at a cemetery in the Peruvian capital of Lima found that at
least some pre-Incan people from the period of A.D. 400 to 1200 also practiced incest.
In the ancient world, incest was generally seen as a serious taboo that violated both cultural rules
and religious laws. But among the Zoroastrians of ancient Iran, the practice of marrying
close family members was sometimes enshrined as a religious ideal that came to be known as xwedodah.
Some writers of the era argued that related parents would love their children more, get along
better with each other, and keep their bloodlines pure. Outsiders who wrote about xwedodah indicated
that it was more likely to be practiced by families of elites in Zoroastrian communities,
such as priests. However, it's possible that members of lower classes might have taken part
in it as well. These sorts of marriages have even worked their way into folktales from the region.
Iran is now a majority Muslim nation,
and Islam generally frowns upon most forms of these marriages. However, first-cousin
marriages are still traditionally considered to be acceptable in some Iranian communities.
The Salt Lake City-based Kingston clan, also referred to as The Order,
the Davis County Cooperative Society, and the Latter-Day Church of Christ,
was founded in 1935 by Charles "Elden" Kingston. It's since reportedly isolated its members with
a mix of racism, apocalyptic fearmongering, patriarchal hierarchy, and anti-government views.
With their links to the early Mormon church, modern Kingston members also practice polygamy.
Elden's brother Ortell reportedly encouraged incest in order to
keep up with the perceived purity of his family to the point that he had children
with two half-sisters and two nieces. His descendants have carried on the tradition,
marrying half-siblings, cousins, and nieces, many of whom were only teenagers.
In 2020, polygamy in Utah was effectively decriminalized between consenting adults. However,
forced marriage and underage marriage are very much causes for a felony conviction.
Spokespeople for the Kingstons have strenuously denied these charges,
but in 2023 the group was given felony convictions for tax fraud.
"The top two defendants in a fraud that stole half
a billion dollars from a biofuel program were sentenced today."
The Kingstons remain tight-lipped about family affairs to the point that members reportedly
fail to list fathers on birth certificates. The closed-off nature of the group has made
investigating the effects of inbreeding difficult. But it has reportedly produced
children with visual impairments, unusually small heads, and dwarfism, among other effects.
According to research published in a 2018 issue of the American Journal of Human Biology,
of the 17 known marriages involving members of Portugal's House of Braganza, eight pairs
were equivalent to those of second-cousin marriages or closer. Moreover, researchers
found that the Braganza lifespan was noticeably shorter compared to the rest of the population.
One of the most eye-catching examples of what was wrought by all this inbreeding could be Maria I,
the first queen to rule Portugal in her own right.
It's not definitively clear if her troubles were due to inbreeding,
though she did experience issues that might be linked to her tangled family tree.
Maria appeared to suffer from manic and depressive episodes accompanied by psychosis,
which might have been diagnosed as bipolar disorder today. Then again,
she lived an especially stressful life that saw the deaths of her husband and oldest son,
as well as the violent French Revolution. When Napoleon Bonaparte invaded Portugal in 1807,
Maria and her family fled the country for Brazil, where she died in 1816.
Though the last known Neanderthals died out about 40,000 years ago, we know a fair amount
about these close human relatives thanks in part to genetics. For example, according to a 2013
study published in Nature, genetic material taken from the 50,000-year-old toe bone of a Neanderthal
woman who lived in the Altai Mountains of Siberia showed that her parents were likely half-siblings.
But why would Neanderthals be so inbred? It's not as if they were building great dynastic alliances
across Ice Age Europe and Asia, as far as anyone can tell. The available evidence indicates that
Neanderthals lived in isolated groups that tended to be relatively small. And that may
have been the issue. With so few potential partners to choose from, Neanderthals may
have found themselves facing a mating lineup that consisted mostly of close relatives.
A 2019 paper in PLoS One suggests that this could've led to a decrease in the reproductive
fitness of the generations that followed, thereby leaving Neanderthal communities with
sinking populations. They would've also been more vulnerable to genetic issues, making them less
resilient than the more genetically diverse modern humans that eventually took over their territory.