[Instructor] In this lecture,
we're going to talk about genetic testing
and look at it across the lifespan,
everything from preconception, prenatal, newborn,
pediatric, adult, and geriatric,
and take a look at how the testing might differ
at each stage of life,
the implications at each stage
and how that might influence a patient's decision
and their healthcare provider's decisions
to pursue certain genetic testing or not.
So just starting here at the beginning, as I mentioned,
we're going to go through really all the stages of life
and look at genetic testing there,
and how the impact can really be quite different
from ethical, legal, and social perspectives,
tying in what we learned last week here.
And so in continuing that discussion
and continuing those thoughts more specifically
in thinking about how genetic testing is done
at each of those stages of life
and how it might differ depending upon the stage of life
where a person is considering genetic testing.
When we're talking about prenatal
or preconception genetic testing, it's typically recommended
for specific diseases known to exist
in the mother or father's family history.
So this is where we'd be thinking,
well, you might be a carrier
for certain rare genetic diseases, for example,
if there is a history of it in one or both
of the individual's family histories
in the couple that's considering having a child.
And this is also true not just with if you have
a specific family history of conditions,
but also this gets back to the ethnicity
or racial group to which the individual belongs,
certainly can have an impact on the likelihood
that they would be carriers for certain conditions.
And there are certain genetic testing panels
that can be ordered that are specifically designed
to test for genetic diseases
that are most common in certain ethnicities or races.
Neonatal screening is mandated by the state
and includes tests for genetic diseases.
These are not genetic tests necessarily.
They're typically biochemical tests
that are performed on the blood sample
that's taken shortly after birth, the heel prick test.
But they often are testing for genetic diseases,
but they're just more so looking for the biochemistry
that you would be able to assess in the blood,
and that would be indicative of a high likelihood
that an individual has a particular genetic condition.
So, as we'll talk about shortly,
that would always be followed up with a reflex test,
what's called a reflex test.
So if it comes back positive in a screen
for a biochemical test,
it would immediately go for more of a specific genetic test.
Pediatric genetic testing occurs
in children demonstrating possible symptoms
of a genetic disease like intellectual disability,
which is commonly associated with a genetic abnormality,
as we've been talking about earlier in the semester.
And this pediatric genetics,
you know, there are some really specific considerations here
because as you can appreciate,
you want to maintain autonomy and decision making
for a genetic test result for an individual.
And in the pediatric setting, you know, it's for a child,
and the child doesn't have the ability
to make an informed decision
at that point until they're an adult.
So the goal is to really try
to save that decision for the child to make
when the child is of age to do that.
The exceptions would be, and we'll talk about this shortly,
but the exceptions will really be
if we're testing for a condition
that the child is going to potentially manifest
during their pediatric stage,
or we could do something to affect the potential progression
of a disease that might manifest later
by having some kind of intervention early on.
Adult genetic testing is a different consideration
after pediatric because again,
now you have the consideration of autonomy
and an individual can decide for his or herself
whether or not they would want
to have a genetic test result.
And we've been talking about this
on the discussion board as well,
I think some great conversations
and just thinking about what would you want to do.
And each patient certainly has the right
to consider that for his or herself,
whether or not they want to know, what they want to know,
when they want to know it.
Because the difference between a genetic test result
and say other kinds of lab results is
that a genetic test result is for life.
When you find out what your particular genetic makeup is
for one gene or set of genes,
or even in the future in your whole genome,
that's not going to change.
So once you know it, you can't really unknow it.
So it's important to really consider it carefully
and for the patient to make that decision for themselves.
Geriatric genetic testing
is actually becoming much more common,
and it may provide useful information
to the patient and their family.
However, common age-related conditions like dementia
are not typically linked with alleles included
in most genetic tests.
So you may have some genetic testing
that is actually helpful
in say, finding the right dose or the right drugs
if there's pharmacogenetic information that's known.
Pharmacogenetics basically just means assessing
a specific set of genes that are typically involved
in metabolism of a drug, of a set of drugs,
and using that to infer how a patient will respond
to a drug therapy and the dosage of a drug therapy.
It's not available for most drugs certainly,
but there are some
that there is some good pharmacogenetic data available
and some good tests that can be run
to help determine ideal dosage,
or the dosage and drug selection
that would be likely to be the safest
and more effective in that particular individual.
And so that's being used in the geriatric population as well
where there are certainly significant risks
to the individual if they get the wrong drug
or the wrong dose.
So let's start at the beginning
or actually before the beginning,
preconception and prenatal testing.
Preconception genetic counseling can be beneficial for those
with a family history of a specific genetic disease
or members of ethnicities or races
with high risk of certain genetic diseases.
We've spoken about the Ashkenazi Jewish population
and that population in particular,
there's a set of genetic diseases
for which they typically have a higher carrier frequency
than in the average population.
And especially if you have both individuals in the couple
that's considering having a child,
if both of them are from the same race or ethnic group
where you do have these higher frequencies of carriers,
then it can be certainly advisable
for that couple to seek genetic counseling
just to better understand the risks
and you know, what their options are moving forward.
Preconception testing is usually for carrier status
because most likely by the time
you're undergoing preconception counseling,
we're talking about adults,
and if they wanted to have tested themselves
for a genetic condition, they're concerned
that they themselves will manifest,
they would've already done it by now, most likely,
not always, but most likely.
But so it's more likely to test for carrier status
because you're not going to be symptomatic
and you wouldn't really know
unless you had this genetic test done.
Prenatal testing typically focuses on testing the fetus
for genetic disease or chromosomal abnormality.
And this could be testing for a specific genetic disease
that's known to run in someone's family
or that's more common in their ethnic group
or those chromosomal abnormalities.
And chromosomal abnormalities, as you remember,
are actually typically a random event
and unlikely to have been inherited,
so unlikely to have run in the family,
but most likely to have just happened rather spontaneously
or as a random event.
In women or couples where you've had many,
say where there's been a higher incidence
of spontaneous abortions,
or if they have had a child
who has had a chromosomal abnormality,
it's probably beneficial for them
to undergo genetic testing
if that's something the couple wants to know.
As with any tests, of course,
what we're talking about here is
that the individual or the family members involved
are all well informed, that they make a decision based
upon that information and knowing what they will do
with that information when the test result comes back.
Same thing for the healthcare providers as well,
knowing what are you going to do
if the result comes back positive or negative
or inconclusive, and being informed
before undergoing the test.
Preconception results may inform
or influence future reproductive decisions,
while prenatal results may inform the decision
to carry to term or help prepare the family
for a child's future care.
So again, when we're thinking about what are we going to do
with this information, that's the part
that needs to be filled in, if possible,
with the information from the couple,
the families, everybody involved
to think through what are they going to do
depending upon the results that come back.
And it still might not be enough
to fully prepare them when the results come back,
but at least they're starting to think about it
and they're making an informed decision
as to whether or not they wish to pursue those tests.
Preconception and prenatal testing
can both significantly impact
the patient's emotional wellbeing and relationships.
And this is of course, critical to keep in mind.
And as we've been talking about in the discussion boards,
it really does kind of come down to a gut feeling
of whether you do or do not want to know something.
And this is the same for prenatal
or even preconception testing.
Some people just will not want to know,
and it would be detrimental to their emotional wellbeing
and potentially to their relationships if they do.
So thinking through it, being very clear, especially going
to see genetic counseling if at all possible,
would be the best option.
Alright, so we're talking about tests here,
and I wanted to throw in a quick reminder if you've seen
this before, hopefully you have,
if not, the concept is relatively straightforward
for our purposes here,
about a diagnostic sensitivity versus specificity.
So we're gonna be talking about testing,
but there's primarily, you can think of two kinds broadly,
two kinds of testing,
one being more of a screen,
which a screen would be looking at a large population
and trying to identify individuals
who are likely to have a disease or a condition
out of the whole big population,
versus a diagnostic test where this is very likely
to be a much smaller population
where there's already reason to believe
someone might have a condition,
there's a suspicion of one sort or another,
whether it's they're demonstrating some kind
of signs or symptoms or there's risk factors associated
with them that would increase the chance
that they would have this condition
or develop this condition.
So you want to keep that in mind.
And those kinds of tests then are very likely
to positively identify those
who indeed do have the condition,
who indeed do have the condition.
So we're talking about sensitivity and specificity
as measures that are reported out
for different diagnostics and screens.
Sensitivity, you can think of
as a measure of a test's ability
to identify those at risk for a condition.
So high sensitivity would be best for screening,
thinking of it as ruling out.
So it's going to come back potentially with a group.
So let's say we're starting
with the whole population of the United States.
Let's say there's 300,
let's just say there's 300 million people in the US
and we're screening every single one of them
for a particular condition.
And what comes back is that it comes back
with 1% of the population.
So 3 million people come back
with a positive result on that screen.
It doesn't mean all 3 million people
have this condition we're screening for.
What it does mean is
that really virtually no one
in the remaining 297 million people
who got a negative result for the screen,
virtually none of them are actually positive.
But in our group that came back as testing positive,
there's likely quite a few who are actually negative,
but they received a positive result on the screen.
Why is this?
Well, we want to have the highest sensitivity for a screen
because we don't wanna miss anybody.
We want to first narrow our group down.
Let's say now we're down to that 1% of the population.
Okay, so now what can we do in that 1% of the population?
Now we can check each of them,
with one of these really high specificity tests,
which is going to basically confirm
or really give us a much more clear diagnosis
that a person has a particular condition.
So in a highly sensitive test,
basically if you get a negative result,
you can feel really confident
that the person truly is negative,
that they don't have this condition.
And that's why we wanna use it for a screen.
We're trying, we're casting, you know, casting a wide net
across the whole population
to make sure that we're not missing anybody
who actually has the condition.
And then if that comes back positive,
there's an immediate reflex test
for a highly specific, a test with high specificity
to confirm the results.
So this would give low false positives.
So now we're gonna take that reduced population
that came back as positive from the screen.
We're gonna test all of them with a different kind of test
that's going to have high specificity
so that we can feel confident that every one of those
that comes back is positive, truly is positive,
truly is positive, okay?
So oftentimes there's several tests
that are grouped together
to confirm that an individual has a particular condition,
especially if it's something like a condition
that we're testing for in the broad population.
Okay, so hopefully that's pretty clear.
You can think of a high sensitivity test as a rule-out test.
So we're trying to, everybody who tests negative,
you can rule yourself out as having that condition.
And high specificity test is a rule-in condition.
So if it comes back positive, you can feel certain
that that person truly is positive.
Ideally, I mean, sure, in a perfect world,
we would want all tests
to be both highly sensitive and highly specific.
The reality is that's very challenging
and certainly is a goal of all diagnostics makers,
but not something that can always be achieved.
Okay, so thinking about some of the risks and cautions
in prenatal testing and screening, false positives,
so this indicates the fetus has a genetic disease
or disorder when that is not the case.
And false negatives, so that would be indicating
the fetus does not have a genetic condition or disorder
that is actually present,
can occur with any genetic test or screen
and must be explained as a possibility to the patient.
So even if something comes back
and it's saying it's positive
or it's a negative result,
usually with every diagnostic, they report back
some kind of an indicator
of the false positive and false negative rate.
And that could be used to help explain those risks
to the patient that's receiving this information.
So all screens that return a positive result
must be followed up with other clinical diagnostics
to confirm, as we talked about,
not just another genetic test,
but also there would any other kind of diagnostics
that can be used to complement that, just to confirm
that the positive result truly is positive.
Some prenatal tests are invasive.
So this is important to keep in mind.
Amniocentesis and CVS in particular are.
CVS in particular is quite invasive.
And each of these types of procedures carries
with it a risk of abortion that can happen,
spontaneous abortion, miscarriage that can happen
as a result of the test itself.
And that risk may not be acceptable
to the patient who's considering it.
All right, cell-free fetal DNA testing.
So if we're trying to move past
the time when we're using amnio and CVS
to test prenatal samples,
we're moving to a time where we're trying to be
as non-invasive as possible.
And this is called non-invasive prenatal testing or NIPT.
It's a promising approach to prenatal genetic testing,
reducing risk to the mother
and fetus from invasive procedures.
And basically all it requires is
to draw a blood sample from the mother
and to sort out the fetal DNA from the mother's DNA.
And it's really interesting,
actually there's DNA
that is basically sort of floating around
in the amniotic fluid that then crosses the placenta
and crosses into the mother,
into the bloodstream of the mother.
So there is some small, small amounts,
very small amounts of fetal DNA.
It's called cell-free because there aren't actually cells,
whole cells from the fetus floating around,
but it's DNA from the fetus,
is again, small amount is floating around
and circulating in the mother's blood.
So if we take a blood draw from the mother,
and using molecular techniques can actually separate
out the maternal from the fetal DNA,
then what you could do is test that fetal DNA
and see you know, what conditions are present
without ever having to invade into the uterus
or take amniotic fluid
or take a sample from the fetus itself,
without any of those invasive procedures.
Basically, you're just taking a blood draw.
So this really is the future of testing.
Obviously it relies upon technologies
to be able to reliably separate fetal DNA
from the maternal DNA.
And that is a challenge,
but that is absolutely the direction that testing is going.
Newborn screening and genetic testing.
So newborn screening is mandated by each state in the US.
And the Department of Health for each of those states is
in charge of determining which conditions
they're testing for and how it's managed.
In the state of Vermont, parents have the right
to refuse screening for any reason.
However, they have to state
that they are refusing screening.
Otherwise the newborn will be screened.
So they have to actively request that it not happen.
They're not asked.
Babies born at home.
And the reason for that is
because it's viewed as a public health issue.
Because if you can catch these conditions early on,
these conditions which often manifest very early,
very soon after birth,
they're commonly metabolic conditions that only manifest
once the child starts feeding in many cases.
Or they're conditions where early intervention
would make a world of difference to the child.
So these are biochemical tests
that are done on the blood.
You can see that in the picture, in the top right corner,
it's what's called a heel prick test.
So the newborn's heel is pricked,
and the blood is collected on a card.
And that card is sent off to the lab and testing is done.
It's usually biochemical type of testing on the blood
to see if there's any abnormalities
in the typical blood biochemistry that might be associated
with certain conditions.
Many of those conditions are genetic conditions,
but this is not a genetic test per se.
It's not actually doing any sequencing here on the screen.
They're just looking for biochemical abnormalities.
And so this is a screen, remember,
so we're looking at the whole population we're screening.
And so when it comes back as positive,
it may or may not actually be positive.
If it comes back as negative, you can feel really confident
that in fact the child does not have that condition.
But if it comes back as positive,
there's a reflex test that's done
with a more highly specific diagnostic for that condition,
usually actual genetic sequencing that would be done
if it's a genetic condition to confirm
that in fact the child does have a genetic condition.
So even if a screen comes back as positive for something,
doesn't necessarily mean it's going to be positive
by the time, you know, all the diagnostics come back in.
Babies born at home, and this happens a lot in Vermont,
babies born at home have newborn screening if requested
by the parents in an office visit.
And Vermont, so in the state of Vermont,
we have 29 conditions in newborn screening.
And you can find a list of those.
There's a link to the Department of Health site
in the reading folder, online resources for this week
if you're interested in checking out the conditions
that are tested for in the state of Vermont.
So how do they decide which conditions go onto a list?
And as I said, each state decides separately.
There are some conditions
that are tested for in every state
but there are other conditions that are not.
And in general, the way screening is determined,
whether or not they're going to screen for a condition is
they use these criteria
that were developed in the '60s actually from a group,
from the World Health Organization,
Wilson and Jungner screening criteria.
And these would include assessing the condition
for whether or not it is a serious health problem,
whether there's accepted treatment available,
if it can be diagnosed, if there're recognizable latent
or early onset symptoms that can be addressed.
There's a suitable test acceptable to the population.
So all of these are really necessary.
If there isn't a suitable test
and if it doesn't work in the population,
it's not going to be something we can include in the screen.
It's a well understood natural history for the condition.
So it's not something so rare
that we don't even understand how the disease works.
There's an agreed policy who is treated.
So if it comes back positive, who would be treated?
Cost of testing and treatment is balanced
to the cost of treating the condition
or testing for the condition individually,
and that there's a continuing process of reassessment
as new data, new treatment becomes available.
So this is one way in which organizations
and departments of health will assess
and decide which conditions are included
in newborn screening.
So the future of newborn screening.
With whole genome sequencing becoming readily available
and cost-effective, the possibility
of newborn genome screening becomes,
or newborn genome sequencing rather becomes real.
So this is an interesting idea, right?
So instead of just testing for one thing at a time,
doing one genetic test at a time,
let's just sequence the entire genome
right from the moment of birth.
Well, it's an interesting idea
and for some it may seem like, well,
this is perfectly logical, let's do that.
And for others it may make you feel queasy
to think about that
as you know, we've talked about autonomy
and the the right to make a decision for yourself
as to what information you do and do not want to know.
Privacy becomes a real question,
and finding out information
about which we can really do nothing
and whether that's valuable or not.
So there are lots of questions to consider here,
but there are a few health centers that are piloting this,
large health centers that are piloting this.
And it's, you know, it's tough to say right now whether
that's the direction we're going to end up going,
but certainly we don't have enough information
to be able to interpret whole genomes,
to know what to do with all of that information yet.
So I don't see it on the five-year horizon certainly,
but looking out beyond that 10, 15, 20 years from now,
it's absolutely a possibility.
And I believe we would need to have a significant amount
of policy in place and clear clinical guidelines,
clear privacy measures to set up to address those concerns
before we would move forward with this.
That would certainly be my hope.
So let's hope that that's how it works
if it does move in that direction.
So now let's move up into a little bit older timeframe.
Now we're talking about pediatric genetics.
So children presenting with symptoms consistent
with a genetic disease may, with parental consent,
undergo genetic testing to aid in diagnosis.
So if a child is complaining, has symptoms, issues,
again, we mentioned intellectual disability
as a common red flag of a genetic disease
which often shows up in pediatric population
as opposed to any earlier than that.
So this would certainly raise the possibility
for genetic testing to aid in diagnosis,
which would potentially lead to better informed treatment.
The American Academy of Pediatrics recommends
the principle factor in making the decision
for genetic testing is whether it is in the best interest
of the child, of the child.
And I think of course,
that's always the best way to go.
Predictive genetic testing is only recommended
for those diseases with onset
or possible intervention during childhood
with parental consent
and when possible with child consent
to best inform the child.
And you know, if they're say in their teenage years,
it may be possible for them to make an informed decision
or to help in that informed decision.
Adult onset predictive disease testing
is not generally deemed to be
in the best interest of the child,
again, to try to retain autonomy
so that the child can make that decision
for his or herself in the future.
And certainly carrier status
is almost universally not pursued in children
as it's only relevant
for family planning for the individual.
So let that individual make that decision for themselves
when they're of age to be able to do that.
Okay, let's move on up to adults.
So in adults, we have genetic diseases
with adult onset may be tested for in the adult population,
and those who have a family history
and have decided to do so.
Often they're sent to genetic counseling
to best understand their risks
and to talk through what are the possible options
for testing, what are the results,
what are the implications,
and just to make sure everyone's well informed
before they make a decision.
Huntington's disease, which we've talked about
a decent amount in this class,
is an autosomal dominant neurodegenerative disease.
And patient may choose to be tested for
if one of his or her parents
or grandparents had Huntington's disease.
But as we talked about last week, I believe,
you know, if a grandparent has Huntington's disease,
and let's say an individual, that individual wants
to be tested, but their parent,
let's say it was their maternal grandfather
who had Huntington's disease,
and then their mother does not want to know
whether or not she has Huntington's disease,
but the child comes of age
and decides that he wants to know.
So he undergoes genetic testing
and finds out he is positive for Huntington's disease.
Then he knows his mother
also has Huntington's disease despite the fact
that she did not agree or decide to have that test done.
So there's a lot of complicating factors,
but you know, at the same time, we can't restrict the right
of that individual to have his genetic testing done.
Once he's an adult, he can decide that for himself.
So there's a balance that has to be sought
whenever we're talking about these ethical situations
and trying to maintain autonomy
and informed consent for everyone involved.
But it's almost impossible in every situation to do that.
So cancer predisposition testing may be recommended
for those with a family history of cancer
or red flags of heritable cancer risk.
And again, they'd likely be sent to genetic counseling
and take a really complete family history, pedigree analysis
and assess what genetic tests are available
for the inheritable forms of cancer.
Carrier status may be tested
in those planning to have children.
So that way it could help to inform their decisions
about whether or not they want
to pursue having children biologically
or if, you know, it may inform the kind of testing
they would want to have done in prenatal testing,
or it can also just help them to better prepare
for the possibility of having a child
with certain conditions.
Okay, moving to the geriatric population,
Alzheimer's disease, age-related macular degeneration
and cancer are common age-related diseases
with a demonstrated genetic component.
So there certainly is rationale for testing
for these conditions in geriatric population.
There's also a rationale for testing.
Let's say if someone in the geriatric population develops
age-related macular degeneration,
there may be reason to have them tested,
undergo genetic testing.
Even though that won't inform
that treatment for that person,
it could help to inform any of their relatives
about their potential risk if it's genetic.
So say a an elderly patient comes in
with macular degeneration
and the thought is, okay, we could do genetic testing
to see if the reason for or part of the contribution
for this macular degeneration is genetic.
It comes back positive.
Then that individual can inform their relatives
of their potential risk of it as well.
And they may undergo genetic testing
to see if they also have the alleles for those diseases.
So it may not be directly helpful
for the health of the person who's getting the test,
but it can help inform the health
and potential future testing of other folks in their family.
Alzheimer's disease, genetic testing is restricted
to select alleles demonstrated to contribute
to early onset Alzheimer's disease,
not late onset Alzheimer's disease or late onset dementia.
So that's really more for developing Alzheimer's disease
before the age of 65.
There is a pretty substantial amount of data
to support there's a genetic component there.
And again, if someone develops Alzheimer's disease,
say 58, 60 years old, it may not help them
to have genetic testing directly,
but it could help to inform their family members
of their potential risk for Alzheimer's disease
from an increased genetic risk, that is.
All right, so some of the results that can come back,
you might just think, well, it's gonna be positive
or it's gonna be negative.
They're gonna say, yes you do, or no, you do not have it.
Unfortunately, there is a third possibility for a result.
And this is not uncommon, not uncommon at all
to get this result, which is the VUS,
variant of unknown significance.
What is that?
Well, it basically means we don't know what the sequence,
what that that person's sequence is going to indicate
in terms of disease or not.
So it means that they sequenced someone's allele
of a gene that's associated
with a particular disease or condition,
and it comes back and the sequence is not wild-type.
It's not one of the typical wild-type sequences
that we commonly see in the population of healthy folks,
but it's also not one of the alleles known
to cause this disease.
So what do you do with that information?
It's a change in the sequence
and it would have to be a change in the sequence
that would result in an amino acid substitution,
so it would either have to be a missense
or nonsense mutation,
so not just a silent mutation because we have tons of those
and they don't matter effectively
because it doesn't affect the amino acid
that's coded for, right?
So that's not really what we're talking about here.
We're talking about a missense or nonsense mutation.
Usually a missense mutation is what we're seeing.
And it's unclear as to whether
or not that could result in the disease.
So then you would get a result
of it's a variant of unknown significance.
We can't tell right now.
And it can be really confusing and frustrating
for a patient who's anticipating coming into the office
and getting an answer.
They probably paid, you know, a decent amount of money
for the test, had to wait six, eight weeks
to get the results.
And they go in to hear
and they're expecting to hear, yes you do, no you don't.
Well, the third option is that it could be we don't know.
And the only thing we can really say to this is
that future research may link that variant
to a specific risk,
but as of today, there's no clear way
to interpret those results.
It could be that it does increase the risk
for this condition
or it could just be a perfectly finely functioning protein
with no real issues
and it's not going to result in the disease at all.
And it's just something, a sequence
that we just haven't come across yet until now,
but we don't really have a better way
to interpret it than that.
And it can be really frustrating as you can imagine,
for patients to get that result.
So is this a good idea?
Reported outcomes in patients following genetic testing.
So BRCA 1/2, there's been reported
there's a temporary stress relieved
beep, temporary stress relieved long-term,
increased surveillance and general improvement
to health long-term in most patients.
So while it might result in the temporary stress,
that is relieved in the longer term,
and that in general does result in better surveillance,
general improvement to long-term health in most patients
who come back with a positive result
for the BRCA 1/2 test.
Alzheimer's disease, neutral to slightly positive impact
on psychological health long-term
for those who decide that they want to have the test
and it comes back positive.
For Huntington's disease, short-term
in the seven to 10 days post results impacts,
worsens depressant scores for those who test positive.
But depression scores improve long-term
for those who test positive and negative.
So if you take the population as a whole,
that's how it averages out.
I will just caution to say, you know,
whenever we're talking about the psychological
or psychosocial impact of anything,
of course each individual has to be considered
in their own context, in their own lives,
in their own wishes.
Because while this, again, this is taken
as an average of the population, that doesn't mean
that for each person it's going to turn out this way.
So, you know, as always, their wishes, their interests,
their understanding of their own situation is
what's most important to consider.
But if we do take the population as a whole,
what we see generally is
that even if the result comes back positive,
people are at least no worse off psychologically
and potentially slightly better off psychologically
and may be more proactive in their health.
Especially when it's something like BRCA 1/2,
where they can actually do something about it,
like going and getting more surveillance, breast exams
and really taking more of an active role
in preventing breast cancer and ovarian cancer.
Okay, so again, considering all possible outcomes
from a test, negative, positive
and that third one, the unknown,
and their impact on the approach to patient's care,
so what are you going to do differently?
What are other healthcare providers going
to do differently with that information?
Positive or negative lifestyle changes,
patient's psychological and emotional welfare.
Where are they now? Where might this lead them?
Patients', family and/or social group
and their support structure,
their understanding of their own health and wellbeing,
and the patient's healthcare coverage and employment,
these are all important to keep in mind.
So the question really comes down
to what will you, the patient's healthcare team
and/or the patient do differently in response
to each of all possible test result outcomes?
And this is commonly what a genetic counselor will walk
through with a patient and their family members,
and just thinking through what are we gonna do
if it's positive?
What if it's negative?
What if it's inconclusive?
And make sure they've thought through everything
before they make a decision on pursuing a test.
So in summary, all stages of life,
genetic testing requires careful consideration
of all possible implications of results
for the patient and their family.
Decisions and actions that may be informed
or influenced by genetic test results differ depending
on the life stage,
and advances in genetic testing technologies
interpretation of results must be approached
with great care for the ethical, social
and legal implications these results can have
on the patient as a whole person.
Okay, well that wraps it up here.
And in the next week,
so once we're wrapped up this module,
we're going to start diving
into some more advanced clinical topics related to genetics
and genomics in these emerging fields,
and give you a taste for a variety
of different areas more specifically.
And we're going to start that off next week
with immunogenetics.
Well, thank you very much for listening to this lecture,
and I look forward to talking with you
on the discussion board.
Take care. Bye.