Science Can Be a Love Story

Julia Mouat
Lab Musings Summer 2018
10 min readJul 30, 2018

Introduction

There are many ways of making three parent children. Adoption, polygamy, divorce and remarriage, surrogacy, artificial insemination, infidelity. These could all produce children with more than two parents, if “parent” is defined in its broadest sense. In February of this year, the United Kingdom claimed the approval of the UK’s first three parent babies. These babies, due later this year, will not be products of divorce or adoption or infidelity. They will be the products of a scientific breakthrough, a science called Mitochondrial Replacement Therapy. In 2014 the United Kingdom’s Parliament and in 2015 the United States’ Supreme Court approved gay marriage. Gay couples, like straight couples, are using adoption and surrogacy. “Three parent babies” are everywhere.

I. Engineers

Mitochondrial DNA is small and circular. Held within the “powerhouse of the cell” this DNA makes up less than 0.1% of the human genome. It does not account for the brown hair you got from your dad’s side when you would have preferred the red from your mom’s. It does not dictate your height, your moral compass, or your IQ. But mitochondrial DNA is crucial for this: making you go, go, go. If the mitochondria to your cells is the engine to your car, then mitochondrial DNA is part of the engineering team designing the engine. Without proper engineering of the mitochondrial powerhouse, the cellular machine is rendered useless, or dangerous.

It is the first day of class, the first day of “Introduction to Gender, Sexuality, and Women’s Studies.” We are twenty twenty-year-old feminists, perched in squiggly rows of desks in a high-ceilinged, light-filled room of the Cathedral. We are twenty feminists, rife with rage, eager for change. That first day, I talk to her, the girl with the glittering blue eyes and impenetrable expression. She tells me she studies civil engineering.

II. Replaceable

Mitochondrial DNA is home to 37 genes, 13 of which code for the cell’s “energy currency,” the combustion chamber of the mitochondrial engine. The other 24 genes are on the assembly line for protein production, the nuts and bolts of the cell. The rest of the engine, the crankshaft, the pistons, the valves, are designed by other engineers, genes that do not reside in the mitochondria.

Months after the awkward civil engineering conversation she tells me she is straight. I stand stock still on the dirt path of Schenley Park, that text message bringing my run to a sudden stop. We have a quasi argument, me rooted to my spot surrounded by the trees of late fall, not far from the stretch of dirt where I broke my ankle a year before. Perhaps I should not run in Schenley anymore. This argument is on her birthday, and in that moment I think we both assume we’ll never speak again. But two days later we are talking again and two weeks later, it is Halloween and we are dating. This sudden, inconceivable change feels conceivable to my heart and I think, to hers as well. I believe our hearts knew we would end up together, our brains only needed time to catch up.

Like a car’s engine, a cell’s mitochondria have many functioning parts working in tandem. In total, there are 3,000 genes designing the mitochondrion, far more than the 37 actually working there. The other 2,963 simply work in the different, much larger factory of the nucleus, whose products are then shipped to the mitochondria. These nuclear genes count 20,000 in total and are to be held responsible for the brown hair you got from your dad’s side; nuclear genes provide the “nature” of the “nature plus nurture” equation. Mitochondrial genes do not make you, you. They just make you go.

She immediately tells her family and friends that we are dating, which takes me by surprise. I expected her to be embarrassed, ashamed, but she is not. Her mom says she is glad because this means Sophie won’t get pregnant. Her dad tells her he will always love her, no matter who she dates. My mom is not surprised, and my dad says he still wants grandkids.

While the mitochondrion is an essential part of the cell, the engineers, the mitochondrial DNA, are nothing special — they must perform their duty of producing a functioning combustion chamber, nothing more, nothing less. The 37 engineers are replaceable.

She is not one of the 37. Her name is Sophie and she is not replaceable.

III. Gender

Sophie says the world of civil engineering is dominated by men, and she is worried. Will they expect nothing of her, or everything? Will they respect her? Harass her? I tell her that in the eyes of mitochondrial DNA, it is a woman’s world: while both men and women have mitochondria, the 37 engineering genes are passed only mother to child. The fertilized egg destroys the father’s mitochondrial DNA, held precariously at the base of the sperm’s tail, almost asking to be ripped away. She says that is interesting but her world is not a mitochondrion’s.

These days, we make coffee and oatmeal in the morning and sit at the high table, a view of the impossibly tall building that housed our meet-cute through the window. We hold hands on the bus on our way to Trader Joe’s, where we always get a package of chicken breast that we freeze at home, then have to scrape off the plastic covering that sticks to the chicken. It is disgusting and we alternate who has to do it. I try to convince her to go running with me. I talk as we walk together, barely paying attention to where we’re going, while she listens and holds my hand, tugging me around corners and guiding me across the middle of the street as I protest that there is a crosswalk half a block down. I wash the dishes and she dries them. She braids my hair and gives me fashion advice and reads my writing. I explain football to her and become confused when I look at her engineering homework. We dance in the kitchen to our favorite playlist. We are boring and we are happy.

IV. Illness

You swing open the door, plop onto the seat, press the brake. You turn the silver key and hear it click but the car only sputters, and shudders, and groans, then goes silent, the only sound that of your heart sinking to the floor.

The human body adds another dimension. There are trillions of cells in the human body, all containing mitochondria. If there is a mistake in the engineering, a mistake in either the mitochondrial or the nuclear DNA that designs the mitochondria, the results are catastrophic, far more than the death of one car. Mitochondrial disease leads to cell death and eventual mass organ system failure. This primarily affects children. At the doctor’s office, upon diagnosis of mitochondrial disease in a child, the heart of a parent ricochets up into the frigid atmosphere, spinning and lost, until suddenly it plunges downward, through the mantle of the earth and into the smoldering core. There was a failure in the engine. The engineers have made a mistake.

She travels for six weeks, to a country I am banned from. As Americans, we are all banned from it, unless with an organized group. This means I am not able to fly there on a whim, which I imagine offers a sense a relief to my parents. The weeks without her feel long, listless, and lonely, as I go through the motions of life while waiting for her messages that pop up for one hour a day, when she pays the hotel $1 for one hour of WiFi.

V. Symptoms

We joke that she passed her migraines to me. She used to get them, now I do. She blackens the room as best she can with our shitty blinds, pours out four ibuprofen tablets every eight hours, guides a bottle of water into my blind hand, and sits next to me with folded legs, massaging my temples, until the balance of pain and hunger finally tips and we go in search of sustenance. For an engineer, she is an excellent nurse.

A migraine is one symptom of mitochondrial disease, a broad term for 200 different diseases, with more being identified all the time. The reason that there are so many? The mitochondria is the powerhouse of the cell — its primary function is to provide energy. But it does many other things as well: it detoxifies ammonia in the liver, metabolizes cholesterol, synthesizes estrogen and testosterone, break down the foods we eat; they are even involved in creating DNA. These functions are unique to specific tissues throughout the body, meaning that when a mitochondrial disease strikes, the possible symptoms are seemingly endless.

Sophie travels for six weeks, six weeks that without her feel long, listless, and lonely. The day after she leaves, I fall ill with a hacking cough, throat full of mucus threatening to suffocate me at every meal, every night. Over the phone Sophie tells me that I am not, under any circumstances, allowed to die.

This guarantee of life is not so with mitochondrial disease. Symptoms of mitochondrial disease can involve the brain (migraines, developmental delays, seizures), nerves (absent reflexes, fainting), muscles (weakness, diarrhea), kidneys (acidosis), pancreas (diabetes), heart (blocks), liver (failure), ears (deafness), eyes (blindness) and others. In each person the symptoms are different but in the bad cases, over time, one organ shuts down, then another, then another.

The term “mitochondrial disease” is itself a lie. It is not one disease — there are over 200 mitochondrial diseases and still counting. However, the underlying mechanism is the same: due to a fault in either mitochondrial DNA or nuclear DNA that codes for the proper functioning of the mitochondria, the powerhouse of the cell does not work properly.

Currently, treatment for mitochondrial diseases is limited to symptomatic management with vitamins and supplements. This is usually quite effective in those with mild cases of mitochondrial disease, and fairly ineffective in those with severe cases. No cure is available.

VI. Solution

There is no cure. But, there is a solution. An effective solution called Mitochondrial Replacement Therapy or MRT that will prevent mitochondrial diseases from occurring in the first place. The procedure can vary slightly but is essentially this: a woman with faulty mitochondria desires a healthy child. The nucleus of her egg is removed, and inserted into a donor egg that contains healthy mitochondria and no nucleus. Though MRT can be called “mitochondrial donation” the procedure is much closer to nucleus donation. This nucleus contains the nuclear DNA of the mother and father, the DNA that makes you, you. The result is a fertilized egg that is over 99.9% genetically matched to the parents, but has healthy mitochondria. This car has a functioning engine, and excellent, if borrowed, engineers.

MRT is not a cure for children that have already been brought into this world. It is a solution for parents hoping to bring healthy children into this world. Most parents who seek out MRT have already lost a child to mitochondrial disease.

The procedure has been approved in Germany and the United Kingdom. In February of 2016, the United States Congress banned the FDA from evaluating any applications that involve implanting modified embryos into a woman. That same month, a report commissioned by the FDA concluded that it is ‘ethically permissible’ to continue clinical investigations of MRT, so long as certain conditions are met. It does not matter so long as Congress’s ban holds: the procedure cannot be performed in the United States.

VII. Ethics

There are ethical debates over MRT. As with any human trials, there are risks involved, for the mother and the child. The techniques have been successful in mice and monkeys, but there is no guarantee that this success will translate to humans.

Critics of MRT, including the Catholic Church, argue that MRT opens the possibility of “designer babies,” where nuclear DNA could be manipulated to produce children that will have that red hair instead of brown. A bioconservative view holds that any genetic manipulation, including MRT, is a form of eugenics.

A non-conservative view contends that MRT is unrelated to the creation of “designer babies,” that MRT producing healthy children that are still genetically matched to their parents.

The UK’s Department of Health has rejected the notions that MRT is genetic modification, and that MRT produces children with three parents.

Still, some say that “three parent babies” are unnatural; some say welcome to modernity.

When we walk down the streets of Pittsburgh holding hands most people don’t take a second glance. Some stare, some whistle, A few have asked, to our dismay, if we are sisters, even twins. Most are either unperturbed, or actively kind. We live in an isolated corner of acceptance. We know that outside of our isolated corner is a sea of people with ethical concerns about our relationship.

VIII. The Future

When I told my parents I have a girlfriend my dad requested grandchildren. I plan to fulfill his wish. Just like a child born through MRT, that child will be a “three-parent baby.” But, in fact, they won’t be. The child will be mine and my partner’s, and a child born through MRT will be the child of its two parents, damn its 0.1% mitochondrial DNA. And, if a child has three parents? So what?

The ethics of medicine and science is usually complicated. But Mitochondrial Replacement Therapy can save lives without affecting the DNA that makes that child the person they are or will grow up to be. It simply gives them the opportunity to grow up.

I am telling you this not because I believe you work for the FDA and have direct control over clinical trials of MRT. I am telling you because there are dilemmas in science and medicine that must be resolved to save lives — MRT being only one of thousands. And these scientific decisions are not made in vacuums, they are not merely the choices of doctors, of scientists, of people at the FDA or politicians. Medical and scientific advancements are guided by public support and perceived societal ethics. This process is slow, but it is true. If we, as a collective, believe that MRT, and other scientific advancements, are the right thing, then our beliefs will eventually become reality, as gay marriage did. Scientific and medical knowledge and opinions are not and should not be restricted to those with MDs and PhDs; it should not be esoteric and elitist — disease affects all of us and we must feel empowered to understand science and influence its implementation. This is a civic duty we share. I encourage you to not shy away from the Science section of the New York Times — it is not as boring or irrelevant as it may seem. Mitochondria are simply the engines of our cells, their journey told through a love story. Science can be a love story, if you make it one.

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Julia Mouat
Lab Musings Summer 2018

I study Microbiology at Pitt, class of 2019. I write about scientific and medical topics that are ethically complex, because what fun is non-complex topics?