Hi, my name is Stephanie, and today I want to talk to you about the concept of a broad autism
phenotype and basically what that is. One of you had actually asked me to go over this and
maybe what constituted the difference between the broader autism phenotype or broad autism phenotype
and autism, and so I thought perhaps I should probably look into that and also explain
what the broad autism phenotype even is, what a phenotype is, etc. So, that's what we're going
to get into in today's video. So, to begin with, let's talk about what a phenotype even is. The
National Human Genome Research Institute defines phenotype as an individual's observable traits,
such as height, eye color, and blood type. The genetic contribution to the phenotype is
called the genotype. So, here they reference this thing called the genotype, and that's basically
your genetic makeup. It's all the genetic information that you have inside of you.
That's what they would call the genotype. So, the genotype and the phenotype are different
because the genotype contains, like, all of our genetic information. So, just because we have
genetic information for something doesn't mean that it's expressed. So, the phenotype is what is
expressed in a person. For example, you probably understand the concept of dominant and recessive
genes, right? So, you might have the genetic information that is required for brown eyes or
blue eyes, however, depending on the mixture of information you have particularly, you might
have brown eyes or blue eyes, but obviously, you might not have both - most people don't,
at least. However, that doesn't mean that that isn't in your genetic makeup and you
could pass that genetic information down to your children just like it was passed down to you.
So, phenotype would be what is expressed; genotype is what you have inside your genetic makeup. Now,
our genetic makeup and the environment interact all the time. An example I hear a lot for this
is the concept of diabetes. So, someone might have the genetic information that would make
them susceptible to having diabetes, however, they might live a lifestyle that actually
causes them to never get diabetes. So, they never have it in their phenotype. Christopher P. Austin,
M.D. explains it this way: Phenotype simply refers to an observable trait.
"Pheno" simply means observe and comes from the same root as the word phenomenon,
and so it's an observable type of an organism, and it can refer to anything from a common trait such
as high or hair color to presence or absence of a disease. Frequently, the term phenotype is used
to relate a difference in DNA sequence among individuals with a difference in trait, be it
height or hair color or disease or what have you, but it's important to remember that phenotypes are
equally or even sometimes more greatly influenced by environmental factors than genetic effects. So,
a phenotype can be directly related to a genotype, but not necessarily. There's usually not a
one-to-one correlation between a genotype and a phenotype. There are almost always environmental
influences which will affect the phenotype as well. So, now that, hopefully, you have a
pretty decent grasp of what phenotype is, let's talk about what broad autism phenotype means.
One article puts it this way: The broader autism phenotype or BAP is a term applied to individuals
with personality and cognitive traits that are similar to but milder than those observed in
autism spectrum disorder or ASD. And another paper says: Termed the broader autism phenotype (BAP),
these traits suggest a genetic liability for autism-related traits in families. Genetic
influence in autism is strong, with identical twins showing high concordance for the diagnosis
and related traits and approximately 20 percent of all ASD cases having an identified genetic
mechanism. So, this paper makes something clear about broad autism phenotype that also kind of
explains a little bit more about what it is: The BAP itself is not a diagnostic entity. In general,
difficulties and differences evidenced in ASD parents and siblings are much milder than those
of their child/sibling with ASD, and do not fall in the clinically significant range. ASD parents
and siblings may demonstrate more BAP features than controls, but the traits, by definition,
do not cause enough functional impairment to justify a clinical diagnosis. So, in general,
it looks like the broad autism phenotype is kind of a term that has been crafted to look into the
amount of genetic influence of autism as well as the family of the autistic person. Something
I personally find interesting is the concept of broad autism phenotype existed before the 2013
change of the DSM, which resulted in the DSM-5 and the creation of the autism spectrum disorder,
which basically put Asperger's and other things on the autism spectrum under one diagnosis. Broader
autism phenotype is kind of this idea of like, trait-bearing people and when they come together,
you know, they might have just some traits and they might have some some traits but when they get
together somehow they start to overlap more and their children might kind of add up to enough to
be autistic, while the parents themselves are not considered autistic. They just have some autistic
traits. So, this really leads me to wonder if some of the people who were considered to be
under the whole broader autism phenotype concept were actually just autistic people,
like autistic parents who hadn't been diagnosed under autism because at the time,
autism was pretty much reserved for higher support needs individuals, those who had severe
impairments in being able to communicate. Maybe they had verbal apraxia and things like that,
maybe they had intellectual disabilities, etc. So, basically, what people might call "severe autism,"
usually that's kind of what autism as a diagnosis was reserved for. So, their family,
not being that same type of autism, were considered under the broad autism phenotype.
So, I do wonder if some of these people actually are autistic under the DSM-5 criteria. However,
this does persist, and research around it persists, after the 2013 change in the criteria
for what constitutes as autism. So, it seems like their goal might be to kind of see how much
of the genotype is expressed in the phenotype. Of course, they've looked into the genotype,
the genetic factors that might cause someone to be autistic for quite a while,
but they're looking into how much is expressed through the phenotype of the family immediately
surrounding the autistic person and how that might affect it appearing specifically as autism rather
than just some autistic traits, therefore, that phenotype. Now, honestly, the difference between
autism and BAP is pretty vague. It's basically the difference between getting an autism diagnosis
and not. The practitioner has to see that autism, or the traits that you are displaying
that would fall under autism, are impairing your life and how you function in your life
enough to be clinically significant to give you a diagnosis. So, this also could be in situations
where someone is just shy of meeting all the criteria
outlined by the DSM-5 for autism. So, maybe they don't see an example of this many things
that have been outlined, and so they're like, well, you know, you have a lot of traits,
but you don't meet all the criteria exactly, so we can't really give you that diagnosis. So,
since you're clearly showing autistic traits that aren't normal in the general population, broader
autism phenotype! Also, if you're wondering why I'm going between "broad autism phenotype" and
"broader autism phenotype," it's because I hear broader even though it's written as broad. I
don't, I don't know. It's just, it's in there. It's in my brain. Just like even in diagnosing
autism, the concept of whether you are autistic or considered under the broad autism phenotype
is just kind of vague and somewhat just a little bit subjective. And I say that because
it depends on the practitioner, obviously, and the information the practitioner has at their disposal
to make that kind of judgment. So, an article by Very Well Health explains why researchers might be
interested in this concept: It is theorized that parents who are part of the broad autism phenotype
are more likely than other parents to have multiple children with autism. This is another
way that researchers can find a way to target autistic children when they're very young kind of
identify them as autistic and basically figure out a way to intervene, whether that is a positive way
with the proper supports and understanding, or whether that is other types of intervention.
The idea and concept of the broad autism phenotype actually can lend to an idea that
a lot of autistic people disagree with, which is we're all a little autistic.
A strong extension of the dimensional approach for autism concerns the autism spectrum hypothesis,
which proposes a broadening of the spectrum so that not only autistic traits in the clinical
population but also within the general population are included. The extension of the autistic trait
continuum into the general population implies the existence of a broad autism phenotype: a continuum
that ranges from individuals who display almost no autistic traits to diagnosed individuals who
are severely impaired. Every single individual exists somewhere on that spectrum and the amount
of autistic traits one exhibits is hypothesized to be correlated with several domains of functioning,
such as cognition, motor skill, and social functioning. What is inherited is not necessarily
clinically diagnosable ASD, but a broad phenotype that is characterized by a symptom continuity
ranging from typicality to autism. This explains why the disorder itself is not often observed in
family members whereas subclinical characteristics are. So, basically, this idea, again, comes to
the concept of people have varying amounts of autistic traits, and if people with higher amounts
of autistic traits get together, then that's going to increase their likelihood of having a
child who is autistic who can be actually clinically diagnosed as such because
their traits are enough and abnormal enough or affects them enough to be considered autism. Now,
this particular idea expressed here would literally put everyone from, like,
typical all the way to severely autistic on the same spectrum, which would actually
mean that everyone is somewhere on the spectrum. Now, there are various methods in which people
have devised to figure out if someone lands in the broad autism phenotype. When compared,
the percentages vary quite a bit. It's just not consistent; the way that it's measured might be
depending on who's reporting what, what kind of measures they use, what were they focusing on,
etc. So, it's a bit messy when it comes to that. I think this is an area where we would greatly
benefit from the ability to do brain scans to find out what really typically looks like autistic
and what might not and if that even exists. Like, how much of a change is there, etc. So, like,
we know that we've seen a distinct differences in autistic versus non-autistic brains,
but obviously, there are measures here where they're saying, well, these traits are present
and those traits are present, so that means you're kind of not, yes, maybe autistic. So,
I think that would be interesting to determine, whether it really is you are autistic or you're
not or you're kind of autistic but you're not autistic enough to be autistic, like this is kind
of saying. So, I actually know someone who has an autistic sibling and they, in many ways, do not
relate to autistic experience and many of the things that autistic people
go through or basically the way we think or do things, etc. Basically, they wouldn't meet the
criteria for an autistic individual. However, they have stated some things to me that sounded very
autistic, especially in certain actions, and I think in that case they would be considered
under the broad autism phenotype. They are a family member of an autistic person who has
autistic traits but really not enough to say, yeah, yeah, that person's autistic. In fact,
they definitely probably would not be diagnosed as such, just from what I personally
know of them. Again, I'm not a professional. I can't diagnose people. But that would be kind of
an argument for the idea of this broad autism phenotype. So, I see the merits of this idea,
where there is a higher incidence, obviously, around the family members of an autistic
individual, and we know, and the people studying this know, that there's a high genetic factor.
So, what causes it to be expressed? And is part of autism being expressed in some people and all of
autism being expressed in the autistic individual? Like, it's very complicated and the implications
around that, I think, are very interesting in defining what autism is. That's just my personal
thought, there. However, I also wonder if some of these people, when you're comparing them to maybe
a higher support needs autistic sibling, don't seem all that autistic when you compare the two,
even if they would actually meet the criteria for autism if they were diagnosed specifically for
that instead of just being ran through a screener for BAP. So, what happens if you're watching this
channel and you suspect maybe you're on the autism spectrum and you go to find out, because, like me,
you might just be curious. You just want to know is it this or not. And you find out that you
don't really meet the criteria. You might just fall under a broader or broad autism phenotype.
Does that mean that, you know, all this information is irrelevant to you or that
you're not valid and all that stuff? I really don't think so. I think that information, when
we can apply it to our lives to maybe understand ourselves better, understand others better,
etc., it's going to be useful and valid. If something that we talk about on this channel
is helpful to you, then it's helpful to you, whether you're autistic or not or somewhere
in between. I don't think that, at the end of the day, it matters a whole lot, if that makes sense.
If you relate to something and it's helpful to you and helpful in understanding yourself,
maybe in understanding other people, improving your relationships, improving
your view of yourself, etc., I don't really personally see that big of an issue with it.
I don't know. I think some people worry too much, like, whether they're allowed to, I don't know,
be in the autism world or whatever. I just think that's kind of ridiculous sometimes. However,
I can see why people would want to be able to define, you know, yes or no in those situations.
So, what do you think about the concept of the broad autism phenotype? This phenomenon
that they're seeing where it's possible that the same genetic information is being expressed in
the phenotype in varying levels around autistic individuals. Do you think that perhaps people
really are maybe a little bit autistic? I am very interested in your thoughts about this. I'll also,
of course, as always, be listing my references in the description box so you can check them out
for yourself. If you enjoyed this video, found it useful and interesting or anything else like that,
you can go ahead and hit the like button and, of course, let me know your thoughts in
the comments below. If you enjoy autism-related content from me, you can go ahead and hit the
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Thank you to everyone who supports me here on YouTube as YouTube members, my patrons over
on Patreon, and a special thank you to my spaz tier patron, Philip Noah. Thank you so much
for watching. I hope you're having a wonderful week, and I will see you in my next video. Bye!