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I grew up in a family with two amazing moms.
My mom Jane gave birth to my brother Jonah, and my mom Deb gave birth to me.
This is a photo of all of us at their wedding day,
after marriage equality was passed in Massachusetts.
But even growing up in liberal Boston, our family structure was still unusual.
To some, it was unnatural.
People even questioned whether we were a real family.
They would say things like, isn't it like weird that you and
your brother aren't biologically related?
No, he's my brother.
Do you wish you knew your dad?
No, I've never thought of my parents sperm donor as my dad.
But like, >> [LAUGH]
>> Do you think you might be gay because
your parents are gay?
Well, I don't know.
Those first two questions were easy, because our family's love,
definitively, did not depend on genetic connection.
But they were frustrating, and
constant reminders of how important genetic connection was to other people.
But that last question really got me thinking.
Because by the time I was 17 years old, even though I had a boyfriend,
I had kind of started to develop a crush on a girl in my school.
So I thought, am I?
And if so, why?
So I set out in search of an explanation.
I opened my computer, and
typed into Google two words, gay gene.
That Google search for an explanation for
my feelings launched a ten year journey of learning about genetics.
I took genetics classes in college, consulted for
genetics companies, and I'm studying it again, here at Stanford.
And I want to share with you what I've learned.
First and foremost, this stuff is really complicated.
A big part of who we are is our DNA and our environment.
Our DNA is the biological matter that carries our genetic code.
And our environment is where we grew up, who we surrounded ourselves with, and
what events happened in our lives.
It would be great if we could hold DNA constant, and
adjust our environment to see which would be more powerful, in which circumstance.
But unfortunately, it's not that simple.
We can ever truly disentangle our DNA from our environment because they're
constantly interacting, and changing each other, and they change us.
So it's futile to ask which is more important,
because it is only through their interaction, that they can change
things like our health, human behavior, and who we are and become.
So I want to walk through three really complex examples to explain how
this works.
And I'm going to break them down into their most essential parts.
Let's start with an example that affects our mental health,
by looking at a study on depression.
Scientists identified a genetic profile linked to depression.
For simplicity, let's call it D gene.
Scientist looked at kids with D gene, and without D gene,
to see why some develop depression and others don't.
They found that kids with D gene, who had negative experiences,
such as the loss of a family member or a serious illness,
were two times as likely as kids without D gene to develop depression.
But they also found that kids with D gene, who had not had negative experiences,
were no more likely than kids without D gene to develop depression.
The lack of an experiential factor essentially equalized the chances that
kids would develop depression, regardless of whether they had D gene.
And we also know that 50% of people with depression have no genetic history for it.
Which means you can have D gene, and never develop depression, or
you can live with depression, and have no genetic connection to it.
So now that we've talked about an example in human health,
let's talk about an example in human behavior, specifically, friendly or
pro-social behavior versus aggressive behavior.
Scientists thought that they'd identified a gene linked to aggression.
Let's call it A gene.
They looked at people with A gene to study the prevalence
of friendly versus aggressive behaviors.
And first, they looked at people with A gene, who had had aversive life events,
such as neglect, in the first two years of their lives.
They found a statistically significant relationship between aversive life
events and exhibiting aggressive behavior.
But interestingly, they also found that people with A gene,
who had had positive experiences,
actually exhibited more friendly behavior than people without A gene.
So had scientists really found the aggression gene, or
had they found the friendly gene?
A gene, itself, doesn't determine whether we'll be friendly or aggressive.
Our environment plays a huge role as well.
When it comes to health and behavior, scientists, presumably,
are looking to get to the root of a problem,
to improve our individual and societal well-being.
But I want to switch gears, and talk about something that
shouldn't be viewed as a problem, but is often studied in the same way.
So now let's get back to what got this whole genetics
research party started, sexuality.
For decades, scientists have tried to find
the gay gene without much success.
They're having trouble testing their hypothesis because first and
foremost, multiple genes are involved in any complex human trait.
Scientists know that a minimum of 2, but
up to 16 genes could influence our eye color alone.
So how could one determine sexuality?
And even when we know the genes that are involved,
our environment plays a huge role as well.
But it's not just testing the hypothesis that's a problem, it's defining it,
that's been challenging as well.
Because what are scientists trying to identify
by finding a gay gene anyway, and why?
Is it who we're capable of being attracted to,
who we're capable of loving, or how we identify?
When it comes to sexuality, there are so many variables involved,
and they're complex, fluid, non-binary, and socially influenced.
So this complicates scientists ability to even define terms like sexuality,
gender, love, attraction, what's genetic, and what's not.
And yet somehow, when I was 17 years old,
I somehow expected those scientists and
their studies to define me.
So why did I do it, why did I Google gay gene?
Why did I think it was so simple?
Why did I need an explanation for my feelings?
Why did I need to know why?
And why does anyone need to know why?
I realize that I Googled gay gene to begin with, because my whole life,
I've gotten question, after question, after question,
that reinforced that our genetics made a real family,
that only genetic connection is legitimate,
that our genetics could predestine who I become.
So we shouldn't use words like genetic or biological or
natural as synonyms for normal, because that's how I internalized them,
and it sent me on a 10 year journey to study something that I ultimately
find really fascinating, but that started as me seeking an explanation for
my feelings, as if they were a problem to be solved.
Now I know that my family, my sexuality, my identity,
they're not problems at all, and they don't require an explanation.
No one should have to Google anything to justify their existence,
because whoever you are, is okay, whether it's found to be true for
you genetically from the beginning, or becomes true for you.
If I've learned anything from all of this, it's that our families,
our identities, our health, our behavior,
basically anything about us, cannot be reduced to genetics alone.
Because humans are so much more complicated than that.
So yes, genetic discoveries have tremendous
potential to benefit humankind, but
genetics does not define our humanity.
Not my mom's, not my brother's, not mine, and not yours.
>> [APPLAUSE]
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