Transcript: June Carroll on Modern Genetics | Oct 19, 2003

(music plays)

A series of images related to the medical field roll from right to left on top of the screen. The name of the show reads "Mini-Med School."

A caption reads "June Carroll. University of Toronto. Modern Genetics."

June is in her forties, with straight brown hair in a bob cut with bangs. She wears a brown printed blouse and a brown blazer.

She stands behind a lectern in front of an audience and says SO, WHEN YOU HEARD I
WAS GOING TO BE TALKING ABOUT
GENETICS, WHAT DID IT MEAN TO
YOU?
WHAT DID YOU THINK ABOUT?
DID YOU THINK ABOUT INHERITED
FEATURES FROM YOUR ANCESTORS?
DID YOU THINK ABOUT, OH, YEAH, I
ACT THE WAY I DO BECAUSE THAT'S
THE WAY THE MEN IN MY FAMILY
HAVE FOR GENERATIONS?
DID YOU THINK ABOUT THE NOSE
THAT YOU HAD INHERITED FROM YOUR
MOTHER?
WHAT DID YOU THINK ABOUT WHEN
YOU THOUGHT ABOUT THAT WORD
"GENETICS"?
DID YOU THINK ABOUT GENETICALLY
MODIFIABLE FOODS?
THAT'S CERTAINLY A TOPIC THAT'S
OUT THERE A LOT RIGHT NOW.
DID YOU THINK ABOUT THE FORENSIC
ASPECTS OF GENETICS, ABOUT DNA
FINGERPRINTING?
THAT CERTAINLY HAPPENS TO BE ONE
OF MY INTERESTS AS A HOBBY, AND
I ACTUALLY LOVE THE SHOW CALLED
"CSI" WHICH IS ON NOW AS WE'RE
TALKING.
[Laughter]

June says IT DOES A LOT OF
CRIME SOLVING THROUGH GENETIC
AND DNA FINGERPRINTING, OR DID
YOU THINK MEDICAL ADVANCES,
ABOUT SOME OF THE NEW GENETIC
TESTS FOR SUSCEPTIBILITY TO
CANCER, TO ALZHEIMER DISEASE, TO
A NUMBER OF COMMON DISORDERS
THAT ARE BEING TALKED ABOUT
NOW?

A slide appears on a screen behind her listing disorders such as heart disease, cancer, stroke, and diabetes.

June says IT'S INTERESTING THAT OF THE TEN
LEADING CAUSES OF DEATH, NINE
SEEMS TO BE CAUSALLY RELATED TO
GENETIC FACTORS, ALL OF THESE
COMMON DISEASES THAT YOU HEAR
ABOUT ALL THE TIME.
THE ONE THAT WE THINK ISN'T,
LET'S SAY INJURY, YOU SAY HOW
COULD THAT BE GENETIC, BUT YOU
PROBABLY HEARD THAT THERE'S SOME
POSSIBILITY FOR A GENE FOR
RECKLESSNESS, RECKLESS
BEHAVIOUR, WHICH PROBABLY A
CONTRIBUTING FACTOR TO A LOT OF
THE INJURY THAT HAPPENS.
SO, YOU MAY SAY, WELL, IS
EVERYTHING GENETIC?
WELL, I WOULD SAY NO, BECAUSE
UNFORTUNATELY ABOUT 50 PERCENT
OR MORE OF THE PREMATURE DEATH
AND DISABILITY IS BY THINGS THAT
WE DO TO OURSELVES OR TO OTHERS,
LIKE, SMOKING, DIET AND
EXERCISE, ALCOHOL, DRUGS.
SO WHAT I'M PLANNING TO TALK
ABOUT IS A LITTLE ON THE HISTORY
OF GENETICS, JUST PARTLY BECAUSE
OF THE DAY THAT IT IS, A PRIMER
ON GENETICS AND SOME OF THE
WORDS THAT WE USE IN THIS AREA.
I'LL TELL YOU A LITTLE ABOUT THE
GENOME PROJECT WHICH I THINK IS
GOING TO CHANGE THE FACE OF
MEDICINE OVER THE NEXT TEN TO
TWENTY YEARS.
WE'LL DO SOME EXAMPLES OF
GENETIC PROBLEMS AND DISORDERS,
AND, PERHAPS, MIKE AND I COULD
HAVE MORE OF A DISCUSSION WITH
YOU ABOUT THAT AFTERWARDS, SOME
OF THE RISKS AND BENEFITS OF
GENETIC TESTING AND MAYBE SOME
OF MY FUTURE PREDICTIONS ABOUT
HOW GENETICS MAY PLAY A ROLE IN
YOUR LIFE.
THE HUMAN GENOME PROJECT, THIS
IS ONE OF THE LARGEST
INTERNATIONAL BIOMEDICAL
RESEARCH PROJECTS EVER AND IT'S
BEEN GOING DONE FOR 15 YEARS.
ITS GOAL IS TO CREATE A HIGH
RESOLUTION MASS OF THESE
APPROXIMATELY 30,000 GENES ON
THE 46 CHROMOSOMES.
AS OF JANUARY THE 5TH THIS YEAR,
THE SEQUENCING WAS ALMOST 96
PERCENT FINISHED.
THIS IS REALLY THE ULTIMATE MAP,
THE SEQUENCE GENES IN OUR
GENOME, BUT BY ITSELF IT'S
REALLY LIKE JUST GIVING YOU A
TELEPHONE BOOK WITHOUT THE
NAMES.
SO, YOU WOULD REALLY GET ALL THE
NUMBERS BUT NOT THE NAMES.
SO, YOU WOULD HAVE A WHOLE LOT
THE CONSEQUENCES BUT NOT REALLY
KNOW WHAT THEY DO.
SO, THE REAL IMPACT IS GOING TO
COME WE ACTUALLY FIGURE HOW TO
MAKE THE WORDS AND SENTENCES AND
HOW TO GET THE MEANING OUT OF
THESE SEQUENCES OF GENES.
WE KNOW NOW THAT THERE'S ABOUT A
THOUSAND GENES THAT ARE
RESPONSIBLE TO SUSCEPTIBILITY TO
DISEASE, BUT WE'VE GOT 30,000
GENES SO THERE'S A LOT OF WORK
TO GO.
SO, HERE'S ANOTHER CLEAR CLAIM
ABOUT SIMILARITIES, HOW ABOUT A
MOUSE AND A HUMAN, HOW SIMILAR
ARE WE AT THE MESSENGER RNA
LEVEL.
YOU'RE PROBABLY ALREADY GETTING
THE GIST OF THIS, SO IT'S NOT SO
MUCH FUN ANYMORE TO GUESS AT
THESE NUMBERS, BUT HERE WE ARE
ABOUT 85 PERCENT SIMILAR AT THE
MESSENGER RNA LEVEL.
IT'S VERY INTERESTING ABOUT THE
MOUSE AND HUMANS.
SOME OF YOU MAY HAVE HEARD ABOUT
THE WHOLE HARVARD MOUSE CASE, THE ISSUE
ABOUT WHETHER A MOUSE THAT CAN
BE USED FOR MEDICAL EXPERIMENTS
SHOULD BE PATENTED.
IT'S INTERESTING THAT THOSE
SPECIES HAVE ABOUT 30,000 GENES
AND ONLY 300 ARE UNIQUE TO THE
HUMAN COMPARED TO THE MOUSE.
SO, THE MOUSE IS ACTUALLY AN
EXCELLENT MODEL FOR HUMAN
DISEASE.
IT DOESN'T HAVE TOO MUCH TO DO
WITH MY TALK BUT IT'S KIND OF AN
INTERESTING PERSPECTIVE ON
GENETICS.
SO, IF YOU'RE INTERESTED IN
THESE KINDS OF TRIVIA ABOUT
GENETICS, IF YOU GO ONTO THE
NATURE WEBSITE, IT'S EASILY
ACCESSIBLE IF YOU JUST PUT IN
NATURE ON YOUR SEARCH, YOU WILL
ACTUALLY BE ABLE TO FIND THIS
ARTICLE ON THE HUMAN GENOME AND
IT ACTUALLY TRACKS THE PROGRESS
OF THE CODING AND SEQUENCING.
I GAVE A SIMILAR TALK IN
NOVEMBER TO THE FIRST MINI-MED
SCHOOL AND I WAS ABLE TO SEE THE
PROGRESS OF GENETIC TRACKING BY
GOING BACK ON IT FOR THIS
TOPIC.
THE QUESTION IS, WHAT THE HUMAN
GENOME... WHAT IMPACT IT WILL
HAVE ON HEALTH PROMOTION AND
DISEASE PREVENTION AND WHAT
IMPACT WILL IT HAVE ON OUR
SOCIETY.
SOME PEOPLE HAVE VERY HIGH HOPES
FOR GENETICS.
SO WHAT IMPACT IS MAPPING THE
GENOME GOING TO HAVE ON HEALTH
AND ILLNESS?
WE ALREADY ARE USING GENETICS TO
DIAGNOSE AND DETECT MANY
DISORDERS.
IN PRENATAL CARE, WE'RE USING
GENETIC TESTING FOR DISORDERS
SUCH AS DOWN SYNDROME, MUSCULAR
DYSTROPHY, NEURAL TUBE DEFECTS.
NEWBORNS AND CHILDREN CAN BE
SCREENED FOR CYSTIC FIBROSIS,
AND THERE IS NOW SUSCEPTIBILITY
TESTING FOR MANY ADULT ONSET
DISORDERS, PARTICULARLY SOME OF
THE CANCERS, SUCH AS BREAST OR
OVARIAN CANCER, COLORECTAL AND
YOU'VE HEARD ABOUT MELANOMA.
WE'RE GOING TO TALK ABOUT THESE
IN A FEW MINUTES.
I WANT JUST TELL YOU A BIT ABOUT
HEREDITARY CANCER FIRST THOUGH.
FIRST OF ALL, IT'S IMPORTANT FOR
YOU TO KNOW THAT ALL CANCERS ARE
GENETIC, AND WHAT I MEAN BY THAT
IS THAT CANCER IS A RESULT OF A
CASCADE OF DNA MUTATIONS IN
SEVERAL GENES THAT ALLOW FOR THE
CELLS TO JUST GROW IN AN
UNCONTROLLED FASHION.
SO, THAT'S REALLY CANCER IS,
CELLS GROWING IN A VERY
UNCONTROLLED FASHION, PROBABLY
RELATED TO GENETIC MUTATIONS,
BUT MOST OF THESE CANCERS ARE
WHAT WE CALL SPORADIC.
SO, WE DON'T KNOW WHAT CAUSED
THEM.
WE DON'T KNOW WHY IT HAPPENED.
THE MUTATION HAS OCCURRED IN
WHAT WE CALL THE SEMATIC CELLS
IN YOUR BODY.
THOSE MUTATIONS ARE NOT PASSED
ONTO YOUR CHILDREN.
WE'VE DEVELOPED THOSE MUTATIONS
PROBABLY AS AN ADULT OR AS A
CHILD AND YOU CAN'T PASS THEM
ON.
THE CANCERS THAT I'M TALKING
ABOUT TODAY ARE WHAT WE CALL
HEREDITARY, AND THAT MEANS THAT
THERE'S A GENE MUTATION THAT'S
IN YOUR GERM-LINE CELLS OR THE
CELLS... THE BASIC ORIGINAL
CELLS THAT ARE BASED ON AS PART
OF YOUR INHERITANCE, SO THROUGH
THE EGG OR THROUGH THE SPERM.
THOSE MUTATIONS CAN BE PASSED ON
THROUGH FAMILIES.
SO, THERE'S QUITE A DIFFERENCE
HERE IN WHAT WE'RE TALKING
ABOUT.
SO, A MUTATION, WHEN I'M TALKING
ABOUT THAT, I'M TALKING ABOUT A
REALLY TERRIBLE ALTERATION IN
THE STRUCTURE OR FUNCTION OF THE
PROTEIN THAT ENDS UP CAUSING
DISEASE.

A slide on the screen reads "Mutation: deleterious alteration in the structure and function of the protein causing disease."

June says SO, YOU CAN SEE THERE'S BEEN
SOME KIND OF TERRIBLE MUTATION
UP HERE IN THE DNA THAT RESULTS
IN AN ERROR IN THE MESSENGER RNA
SO THAT THE PROTEIN IS ALTERED.
IN MOST CASES, IT MEANS THAT THE
PROTEIN IS TRUNCATED OR
SHORTENED SO THAT IT'S UNABLE TO
CARRY OUT ITS PROPER FUNCTION.
SO, HOW WOULD YOU KNOW IF YOU
WERE PART OF ONE OF THESE
HEREDITARY CANCER FAMILIES THAT
I'M TALKING ABOUT?
WELL, YOU WOULD PROBABLY HAVE
SEVERAL RELATIVES ON THE SAME
SIDE OF THE FAMILY WHO HAVE
CANCER.
MORE THAN ONE GENERATION WOULD
BE AFFECTED WITH THE SAME KIND
OF CANCER OR VERY SIMILAR
CANCERS, AND USUALLY THE CANCER
WOULD HAVE BEEN DIAGNOSED AT A
YOUNG AGE, SO IN PEOPLE WHO
YOUNGER THAN 50 AND PARTICULARLY
IF THERE ARE CANCERS IN THE
FAMILY UNDER THE AGE OF 35.
THAT WOULD RAISE, SORT OF, A RED
FLAG THAT YOU MIGHT BE FROM A
HEREDITARY CANCER FAMILY.
TAKE A LOOK AT MARY, FOR EXAMPLE
HERE.
HERE'S MARY WHO IS 40.

A family tree appears on a slide with the caption "Mary’s family tree: highlighting family members with breast or ovarian cancer."

June says SO, SHE HAS A MOTHER WHO DIED OF
OVARIAN CANCER AT THE AGE OF 48.
SHE HAS A SISTER WHO WAS
DIAGNOSED WITH OVARIAN CANCER AT
THE AGE OF 40, AND HE HAS
ANOTHER SISTER WITH BREAST
CANCER DIAGNOSED AT THE AGE OF
38.
SHE HAS A NIECE WHO WAS
DIAGNOSED WITH BREAST CANCER AT
THE AGE OF 30.
THESE ARE THE KIND OF FAMILIES
THAT WOULD RAISE A FLAG FOR A
FAMILY DOCTOR OR A CANCER
SPECIALIST THAT THIS MIGHT BE AN
INHERITED FORM OF BREAST OR
OVARIAN CANCER.
YOU CAN SEE WHY.
IT'S MULTIPLE GENERATIONS,
PEOPLE AT A YOUNG AGE GETTING
BREAST OR OVARIAN CANCER.
SO, WHAT ARE THE ISSUES FOR
MARY?
WELL, I'M SURE SHE HAS A LOT OF
QUESTIONS.
HAS SHE INHERITED THIS DISEASE?
IS SHE LIKELY TO GET BREAST OR
OVARIAN CANCER?
WHAT ABOUT HER DAUGHTER AND HER
SONS?
WHEN SHOULD HER DAUGHTERS START
HAVING MAMMOGRAMS?
WHAT SHE DO ABOUT THIS?
WHAT ADVICE SHOULD SHE GIVE HER
BROTHER WHO MAY ALSO HAVE
INHERITED THIS?
HAS HE PASSED IT ONTO HIS
DAUGHTERS?
THESE ARE THE KIND OF QUESTIONS
THAT ARE RAISED IN THIS KIND OF
SITUATION.
FIRST OF ALL, WHAT'S THE AVERAGE
WOMAN'S CHANCE OF GETTING BREAST
IN HER LIFETIME?
THIS IS THE NUMBER MANY OF YOU
WILL KNOW, WHICH IS THE ONE IN
NINE.
LET'S JUST TAKE ABOUT BREAST
CANCER FOR A MINUTE.
EIGHTY PERCENT OF WOMEN HAVE AN
AVERAGE RISK OF BREAST CANCER
WHERE THE CAUSES ARE KNOWN AND
AGE IS STILL THE BIGGEST RISK
FACTOR FOR GETTING BREAST
CANCER.
SO, THE OLDER A WOMAN GETS, THE
HIGHER RISK SHE IS OF GETTING
BREAST CANCER.
TWENTY PERCENT OF WOMEN HAVE A
FAMILY HISTORY OF BREAST OR
OVARIAN CANCER, AND IF YOU HAVE
ONE FIRST-DEGREE RELATIVE, AND A
FIRST-DEGREE RELATIVE MEANS A
PARENT, A SIBLING OR A CHILD,
WHO HAS BREAST OR OVARIAN CANCER...
SORRY, IF YOU HAVE ONE
FIRST-DEGREE RELATIVE UNDER 50
WITH BREAST CANCER, YOU HAVE TWO
TIMES THE RISK OF GETTING BREAST
CANCER.
HERE'S THE PEOPLE WE'RE TALKING
ABOUT IN THIS TALK ABOUT THE
HEREDITARY CANCER SYNDROMES.
ABOUT FIVE PERCENT OF WOMEN WITH
A FAMILY HISTORY WILL HAVE
HEREDITARY BREAST CANCER WHERE
THEY'VE INHERITED A GENE
MUTATION THAT PUTS THEM AT
INCREASED RISK OF GETTING BREAST
OR OVARIAN CANCER.
WE'VE NOW DISCOVERED MORE THAN
400 MUTATIONS IN THE TWO GENES
THAT SEEM TO BE RESPONSIBLE FOR
THIS HEREDITARY BREAST CANCER.
THESE GENES, WHEN THEY'RE
FUNCTIONING PROPERLY, STOP THE
GROWTH OF TUMOURS.
THEY REPAIR DAMAGED DNA.
SO, WHEN THEY'RE MUTATED,
THEY'RE UNABLE TO REPAIR THE
DAMAGED DNA AND TUMOURS CAN
GROW.
SO, WHO HAS THESE MUTATIONS?
THE FREQUENCY OF THIS MUTATION
IS ABOUT ONE IN A THOUSAND IN
THE GENERAL POPULATION, AND
ABOUT ONE IN FIFTY IN ASHKENAZI
JEWS.
THESE ARE JEWISH PEOPLE WHO HAVE
USUALLY ORIGINATED IN NORTHERN
EUROPE.
EACH CHILD OF SOMEONE WHO
CARRIES THIS MUTATION HAS A
FIFTY PER CHANCE OF HAVING IT
THEMSELVES.
SO, WHAT DOES IT MEAN IF YOU
CARE THE GENE FOR HEREDITARY
BREAST CANCER?
WELL, THERE'S AN INCREASED RISK
OF GETTING BREAST CANCER UP TO
ABOUT 85 PERCENT RISK OF GETTING
BREAST CANCER BY THE AGE OF 70,
COMPARED TO 11 PERCENT RISK IN
THE GENERAL POPULATION.
YOU CAN SEE WHAT A HUGE
DIFFERENCE IT MAKES HAVING THIS
MUTATION.
THEY HAVE AN INCREASED RISK OF
OVARIAN CANCER, UP TO ABOUT 40
CHANCE OF GETTING OVARIAN CANCER
BY THE AGE OF SEVENTY COMPARED
TO LESS THAN ONE PERCENT OF THE
GENERAL POPULATION.
MEN ARE NOT IMMUNE TO THIS.
IF THEY'VE INHERITED THE
MUTATION, THEY HAVE UP TO 15
RISK OF PROSTATE CANCER COMPARED
TO THREE PERCENT IN THE GENERAL
POPULATION.
A COMMON MYTH IN GENETICS IS
PEOPLE THINK THAT WOMEN INHERIT
FROM THEIR MOTHERS AND MEN
INHERIT FROM THEIR FATHERS, OF
COURSE, NOT TRUE, AS YOU INHERIT
EQUALLY.
SO A MAN HAS A 50 PERCENT CHANCE
OF INHERITING THE HEREDITARY
BREAST OR OVARIAN CANCER GENE
FROM HIS MOTHER OR HIS FATHER
AND CAN PASS THAT ONTO HIS
CHILDREN.
ANOTHER MYTH, JUST WHILE WE'RE
ON MYTHS, IS THAT YOU'VE
INHERITED THE SAME GENES AS THE
PARENT YOU LOOK THE MOST LIKE.
WELL, YOU'VE INHERITED SOME OF
THEM, BUT YOU CERTAINLY HAVEN'T
INHERITED ALL OF THEM.
SO, OBVIOUSLY IT DOESN'T MEAN
YOU'RE GOING TO BEHAVE THE SAME
WAY MEDICALLY.
SO, WHAT CAN GENETIC TESTING FOR
SUSCEPTIBILITY TO CANCER TELL
YOU?
WELL, IF YOU HAD A POSITIVE
GENETIC TEST FOR ONE OF THESE
INHERITED CANCER SYNDROMES, IT
OBVIOUSLY TELLS YOU YOU'RE AT
INCREASED FOR THAT SPECIFIC
CANCER.
THE PROBLEM THOUGH WITH GENETIC
TESTING TODAY IS, FIRST OF ALL,
IT DOESN'T TELL YOU WOULD GET IT
FOR SURE.
SO THE RISK OF GETTING BREAST
CANCER IF YOU CARRIED THIS GENE
MUTATION RANGES ANYWHERE BETWEEN
ABOUT 45 AND 85 PERCENT.
IT ALSO DOESN'T TELL YOU WHEN
YOU'LL GET IT, WHAT AGE.
ARE YOU GOING GET IT AT FIFTY,
OR ARE YOU GETTING TO GET IT AT
NINETY AND IT DOESN'T TELL YOU
HOW BAD THE CANCER WILL BE.
SO, YOU CAN SEE IT'S PRETTY
INEXACT AND CAN CAUSE A LOT OF
ANXIETIES BECAUSE WE JUST DON'T
HAVE THE ANSWERS.
A NEGATIVE GENETIC TEST, IF YOUR
FAMILY HAS A KNOWN GENETIC
MUTATION, TELLS YOU THAT YOU
HAVE THE SAME RISK OF GETTING
THAT TYPE OF CANCER AS THE REST
OF THE POPULATION.
THIS IS PRETTY COMPLICATED SO
WE'RE GOING TO GO THROUGH A
LITTLE MORE ABOUT THIS IN A
MAIN.
JUST AS ANOTHER EXAMPLE,
COLORECTAL RECTAL CANCER IS
ANOTHER INHERITED CANCER KIND OF
SYNDROME, AND YOU'LL SEE THE
PATTERN IS VERY SIMILAR TO
HEREDITARY BREAST CANCER.
THE CHANCE OF GETTING COLORECTAL
CANCER IN YOUR LIFETIME NORMALLY
IS ABOUT SIX PERCENT AND ABOUT
75 PERCENT OF PEOPLE ARE AT
AVERAGE RISK OF GETTING COLON
CANCER.
TWENTY PERCENT OF PEOPLE HAVE
COLON CANCER IN A FIRST-DEGREE
RELATIVE.
IF YOU HAVE ONE FIRST-DEGREE
RELATIVE OF COLON CANCER, YOU'RE
AT TWICE THE RISK, BUT IF YOU
HAVE ONE FIRST-DEGREE RELATIVE
OF COLON UNDER 45, YOU HAVE FIVE
TIMES THE RISK.
SO, AGAIN IF IT'S AT A YOUNGER
AGE, IT MAKES A DIFFERENCE.
FIVE PERCENT SEEM TO HAVE THIS
HEREDITARY COLORECTAL CANCER
SYNDROME AND THAT MEANS THEY
CARRY A GENE THAT PREDISPOSES OR
MAKES THEM MORE SUSCEPTIBLE TO
GETTING YOU COLORECTAL CANCER,
AND THEY THEN HAVE AN 80 PERCENT
RISK OF GETTING COLON CANCER.
SO, WHAT SHOULD YOU DO IF ANY OF
THESE STORIES SOUND LIKE YOUR
FAMILY?
YOU SHOULD CERTAINLY TALK TO
YOUR FAMILY PHYSICIAN ABOUT YOUR
FAMILY HISTORY, AND IF YOU'RE AT
INCREASED RISK, IF YOU MEET SOME
OF THE CRITERIA THAT ARE LAID
OUT FOR THESE HIGH RISK
FAMILIES, YOU MIGHT CONSIDER
BEING REFERRED TO A GENETIC
CENTER TO SEE A SPECIALIST, A
GENETICIST OR A CANCER
SPECIALIST WHO SPECIALIZES IN
THIS AREA.
THE GENETIC TESTING IS
AVAILABLE, IT'S CERTAINLY
AVAILABLE AT MANY CENTERS IN
TORONTO AND AT A NUMBER OF
REGIONAL GENETIC CENTERS.
GENETIC TESTING ITSELF IS VERY
SIMPLE FOR YOU IN THAT IT'S ONLY
A BLOOD TEST, BUT IT'S NOT SO
SIMPLE IN ITS IMPLICATIONS.
IT'S COVERED BY OHIP IF THE
CRITERIA ARE MET FOR TESTING.
SO, THE BASIC PROCESS UNDER
WHICH YOU HAVE TO GO IS THAT IF
YOU WERE INTERESTED IN HAVING
THIS TESTING AND YOU THOUGHT HAD
A FAMILY HISTORY WITH THIS KIND
OF RISK, A PERSON IN YOUR FAMILY
NEEDS TO BE TESTED FIRST WHO
ACTUALLY HAS CANCER.
LOOKING FOR THE GENETIC MUTATION
IS LIKE LOOKING FOR AN NEEDLE IN
A HAYSTACK.
IF YOU KNOW THE NEEDLE IS LIKELY
TO BE THERE, YOU'RE MORE LIKELY
TO GO LOOKING FOR THAT PERSON
FIRST.
SO, THAT, FOR INSTANCE, WITH
MARY IN MY STORY, IF ONE OF HER
RELATIVES WITH CANCER WAS
WILLING TO HAVE GENETIC TESTING,
SHE WOULD BE THE FIRST PERSON
TESTED, AND IF A MUTATION WAS
FOUND, THEN TESTING WOULD BE
OFFERED TO THE REST OF HER
FAMILY MEMBERS.
IT'S ONLY IN EXCEPTIONAL
CIRCUMSTANCES THAT PEOPLE CAN
HAVE GENETIC TESTS WHERE THERE
ARE NO FAMILY MEMBERS LIVING
WITH CANCER WHO ARE WILLING TO
BE TESTED.
WE WON'T GO INTO THOSE IN DETAIL
BUT PARTICULARLY IN THE
SITUATION OF ASHKENAZI JEWS
WHERE THERE MAY NOT BE FAMILY
MEMBERS LIVING, THERE ARE
PARTICULAR GENE MUTATIONS THAT
CAN BE TESTED FOR.
SO, WHAT ARE THE RISKS OF
GENETIC TESTING?
I MEAN WHY WOULDN'T ALL OF YOU
WANT TO HAVE GENETIC TESTING?
WELL, I CERTAINLY WOULDN'T
ADVISE THAT, FIRST OF ALL, AND
WHAT YOU'RE GOING TO SEE IN MY
EXAMPLES... FIRST I'VE PRESENTED
CANCERS.
I'M GOING TO PRESENT A COUPLE OF
OTHER EXAMPLES.
THESE CANCERS, THESE TWO CANCERS
ARE REALLY THE ONLY CANCERS THAT
ARE NOW BEING TESTED FOR... I
GUESS, OTHER THAN MELANOMA.
SO, WE DON'T HAVE TESTS FOR
EVERY KIND OF CANCER, THAT'S THE
FIRST THING.
IF YOU HAD A NEGATIVE TEST, YOU
MIGHT THINK THAT YOU'D JUST BE
THRILLED TO FIND THAT YOU DIDN'T
CARRY THE MUTATION, BUT WHAT
WE'VE FOUND IS THAT OFTEN IN
THESE FAMILIES PEOPLE FEEL VERY
GUILTY.
THEY SUFFER FROM WHAT WE CALL
"SURVIVOR GUILT" WHERE MANY
MEMBERS OF THEIR FAMILY HAVE
DIED OF A PARTICULAR KIND OF
CANCER AND THEY WONDER WHY THEY
WERE SPARED AND PERHAPS THEIR
SIBLINGS OR PARENTS ARE NOT.
THERE'S THE RISK OF COMPLACENCY.
PEOPLE THINK IF THEY DON'T HAVE
THE GENE MUTATION, THEY DON'T
HAVE TO DO THE REGULAR
SCREENINGS OR MAMMOGRAMS OR
EXAMINATIONS.
MANY OF THESE GENETIC RESULTS
ARE UNCERTAIN.
JUST BECAUSE A MUTATION ISN'T
FOUND, LET'S SAY IN MARY'S
FAMILY NO MUTATION IS FOUND, IT
MAY MEAN THAT WE JUST HAVEN'T
FOUND THAT MUTATION YET.
WE'VE ONLY FOUND ABOUT 400 AT
THIS POINT.
POSITIVE TEST RESULTS OFTEN
RESULT IN ANXIETY, DEPRESSION,
GUILT AT PASSING ON THE GENETIC
MUTATION TO YOUR CHILDREN.
THERE CAN OFTEN BE MAJOR FAMILY
ISSUES.
IT MAYBE THAT PERHAPS A FELLOW
IN A FAMILY FINDS OUT THAT HE'S
CARRYING THE GENE FOR HEREDITARY
COLORECTAL CANCER AND THEN HE
HAS THE RESPONSIBILITY OF
NOTIFYING OTHER MEMBERS OF HIS
FAMILY.
THEY MAYBE FAMILY MEMBERS THAT
YOU'RE NOT CLOSE TO ANYMORE.
YOU MAY HAVE HAD MAJOR ARGUMENTS
WITH THEM AND YOU DON'T TALK
ANYMORE.
A SIBLING MAY NOT WANT TO KNOW
THEIR TEST RESULTS.
I MEAN ALL KIND OF THINGS CAN
START TO HAPPEN IN FAMILIES WHEN
YOU TALK ABOUT THESE THINGS.
THESE TESTS ARE DIFFERENT THEN
JUST HAVING YOUR HEMOGLOBIN
MEASURED OR YOUR BLOOD SUGAR
BECAUSE THEY HAVE RAMIFICATIONS
THROUGH YOUR WHOLE FAMILY.
IF YOU HAVE THE TEST AND FIND
OUT YOU HAVE THE MUTATION,
EVERYONE ELSE IN YOUR FAMILY MAY
POSSIBLY BE CARRYING THAT
MUTATION, AND THEY MAY NOT HAVE
WANTED TO KNOW, THANK YOU VERY
MUCH, BUT YOU'VE NOW TOLD THEM.
THERE MAYBE ISSUES ABOUT
INSURANCE.
FORTUNATELY IN THIS COUNTRY IT'S
NOT GOING TO AFFECT YOUR HEALTH
INSURANCE, BUT IN THE UNITED
STATES THIS IS A HUGE ISSUE, AND
A NUMBER OF PEOPLE ARE NOT
CHOOSING TO HAVE TESTING BECAUSE
THEY THINK IT WILL AFFECT THEIR
HEALTH INSURANCE.
THERE'S ALSO, OF COURSE, THE
ISSUES OF CONFIDENTIALITY AND
PERHAPS WE CAN TALK ABOUT THAT
LATER, BUT IF YOU THINK ABOUT
THE SITUATION WHERE I'M A FAMILY
DOCTOR FOR A WHOLE EXTENDED
FAMILY AND ONE PERSON CHOOSES TO
HAVE GENETIC TESTING AND FINDS
OUT THEY'RE POSITIVE AND ASKS ME
NOT TO TELL ANYBODY ELSE.
SO, WHAT DO I DO WITH THE REST
OF THE FAMILY MEMBERS WHO I NOW
KNOW COULD BE AT INCREASED
RISK?
THEY'RE GOING TO WONDER WHY I'M
ORDERING MAMMOGRAMS AT 30
INSTEAD OF AT 50.
I MEAN, IT'S GOING TO SEEM
PRETTY WEIRD, AND IF I DON'T
ORDER THEM, HOW AM I GOING TO
FEEL WHEN I KNOW THAT THEY COULD
BE AT INCREASED RISK.
SO, THERE'S HUGE IMPLICATIONS
HERE THAT NO ONE HAS REALLY
THOUGHT ABOUT YET OR KNOWS WHAT
TO DO.
SO, YOU MIGHT HAVE GENETIC
TESTING BECAUSE IF IT WAS
NEGATIVE YOU WOULD BE RELIEVED
FROM SOME ANXIETY.
YOU MIGHT BE PREVENTED FROM
HAVING UNNECESSARY SURGERY FOR
TREATMENTS, AND A POSITIVE TEST
RESULT MIGHT MEAN THAT YOU COULD
BENEFIT FROM INCREASED
SURVEILLANCE OR PREVENTATIVE
OPTIONS.
SO IF YOU FOUND OUT THAT YOU HAD
THE GENE FOR HEREDITARY BREAST
CANCER, YOU WOULD PROBABLY START
MAMMOGRAPHY AT THE AGE OF 25.
YOU WOULD PROBABLY HAVE
ULTRASOUND SURVEILLANCE FOR
OVARIAN CANCER SCREENING AT 25
OR 30.

A slide on the screen reads "If you found out you had the gene for Hereditary Breast Cancer" Breast surveillance (annual mammography starting at age 25), ovarian cancer screening (ultrasound starting age 25-30), surgery, medications and lifestyle changes."

June says THERE'S ALMOST NO EVIDENCE AT
THE MOMENT FOR ANY OF THESE
RECOMMENDATIONS I'M GIVING YOU
BECAUSE IT'S JUST TOO SOON.
SO, THESE RECOMMENDATIONS ARE
REALLY BASED ON THE ADVICE OF
EXPERTS AND THE EXPERIENCE WE
HAVE SO FAR, BUT WE WON'T HAVE
THE RESULTS OF THESE RANDOMIZED
TRIALS REALLY FOR ANOTHER FEW
YEARS.
IF YOU FOUND OUT YOU HAD THE
GENE FOR HEREDITARY COLORECTAL
CANCER, YOU'D PROBABLY START
COLONOSCOPY AT ABOUT THE AGE OF
25 OF FIVE YOUNGER THAN THE
RELATIVE WHO HAD THE EARLIEST
DIAGNOSIS.
YOU CAN SEE THESE ARE MUCH
EARLIER INTERVENTIONS THEN YOU
WOULD HAVE IF YOU DIDN'T HAVE
THE GENE MUTATION.
WE KNOW THAT ABOUT TEN PERCENT
OF PEOPLE OVER 70 HAVE MEMORY
LOSS, AND PROBABLY ABOUT 50
PERCENT OF THESE HAVE
ALZHEIMER'S DISEASE.
I'M SURE YOU'RE FAMILIAR WITH
THE SYMPTOMS FROM THE TALK YOU
HAD LAST SESSION.

A slide on the screen lists the symptoms: memory loss, poor judgement, agitation, confusion, language disturbance and withdrawal.

June says AND YOU KNOW
THAT THE CAUSES INCLUDE, AGING,
GENETIC PREDISPOSITION, AND
PERHAPS EXPOSURE TO SOME OF
THESE ENVIRONMENTAL AGENTS.

A slide appears that reads "Genetic Testing for Alzheimer Disease."

June reads the slide and says NOW, LET'S TALK ABOUT GENETIC
TESTING FOR THIS DISORDER.
FIRST-DEGREE RELATIVES, AND
REMEMBER THAT MEANS A PARENT, A
SIBLING OR A CHILD, OF PEOPLE
WITH ALZHEIMER'S DISEASE HAVE A
LIFETIME RISK OF 20 TO 25
PERCENT OF GETTING IT
THEMSELVES.
SO, THAT'S TWICE THE USUAL RISK,
AND THERE IS A GENETIC BASIS,
THIS APO-LIPO PROTEIN E-4 IS
ASSOCIATED WITH ALZHIEMER
DISEASE.
HAVING IT DOES NOT MEAN THAT
YOU'RE NECESSARILY GOING TO GET
ALZHEIMER'S AND NOT HAVING IT
DOESN'T MEAN THAT YOU WON'T GET
ALZHEIMER'S DISEASE.
SO, HERE'S THE REAL DILEMMA WITH
THIS KIND OF GENETIC TESTING,
WOULD YOU WANT TO HAVE A GENETIC
TEST THAT WOULD TELL YOU THAT
YOU HAVE THE GENE MARKER OR YOU
YOU HAVE THE GENETIC MUTATION
FOR ALZHEIMER'S DISEASE, BUT WE
CAN'T TELL YOU WHETHER YOU'RE
GOING TO GET IT OR WHEN YOU'RE
GOING TO GET IT AND WE CAN'T
TREAT IT REALLY.
SO WOULD YOU WANT TO KNOW?
SO, FOR ME THIS AN EXAMPLE OF A
GENETIC TEST THAT'S NOT REALLY
READY FOR PRIME TIME AT THIS
TIME.
NOW WHEN I PRESENTED THIS IN
NOVEMBER, A NUMBER OF PEOPLE
CAME UP TO ME AFTERWARDS AND
DISAGREED WITH ME ON THIS.
AN ELDERLY GENTLEMAN IN THE
AUDIENCE SAID THAT HE WOULD
ACTUALLY WANT TO HAVE THE TEST,
BECAUSE IF HE KNEW THIS WAS
LIKELY TO HAPPEN TO HIM HE WOULD
GET HIS AFFAIRS IN ORDER AND HE
WOULD JUST FEEL BETTER.
HE WOULD KNOW WHAT WAS LIKELY TO
HAPPEN TO HIM.
HE WOULD PREPARE THINGS WITH HIS
FAMILY, WHICH I THINK IS FAIR
ENOUGH, BUT, AGAIN, REMEMBER
THAT THE TEST DOESN'T JUST APPLY
TO YOU.
SO, IF YOU HAVE THE TEST AND YOU
FIND OUT THAT YOU'RE CARRYING
THE GENE FOR ALZHEIMER'S
DISEASE, YOUR 16-YEAR-OLD GREAT
GRANDSON NOW KNOWS THAT HE HAS
QUITE A POSSIBILITY OF GETTING
THIS TOO, AND HOW WOULD THAT
AFFECT HIS LIFE?
WOULD HE CHANGE HIS EDUCATIONAL
PLANS, YOU KNOW, HIS LIFE'S
DREAM BECAUSE YOU DON'T KNOW IF
YOU'RE GOING TO GET IT OR WHEN
YOU'RE GOING TO GET IT AND WE
CAN'T STOP IT.
SO, I THINK WHEN YOU HEAR ABOUT
THESE NEW GENETIC TESTS THAT
YOU'RE GOING TO HEAR A LOT ABOUT
IN THE NEWSPAPER AND MAGAZINES
AND ON THE RADIO AND T.V., I
THINK YOU HAVE TO THINK ABOUT
EACH TIME, WHAT DOES IT MEAN?
HOW CERTAIN IS IT?
IS THERE ANYTHING I CAN REALLY
DO ABOUT IT THAT WOULD MAKE A
DIFFERENCE, AND DO I REALLY WANT
TO KNOW?
IF YOU CAN ANSWER ALL THOSE AND
IT MAKES SENSE, THEN GO AHEAD
THINK ABOUT HAVING IT, BUT THESE
ARE VERY COMPLICATED AND VERY
DIFFERENT THAN MEDICINE HAS BEEN
UNTIL NOW.
THIS SLIDE I THINK JUST GOES
THROUGH WHAT I JUST SAID.
SO, IN SPITE OF WHAT I'VE JUST
SAID, THERE'S THE OCCASIONAL
FAMILY HISTORY THAT'S STRIKING
IN THE SENSE OF ALZHEIMER'S
DISEASE HER WHERE PEOPLE ARE
GETTING IT AT VERY YOUNG AGES
AND VERY COMMONLY, AND I THINK
IN THOSE SITUATIONS IT IS WORTH
AT LEAST DISCUSSING IT WITH A
GENETICIST SO YOU GET YOUR
INDIVIDUAL RISK AND DECIDE
WHETHER YOU WANT TO HAVE TESTING
OR NOT.
SO, YOU CAN CERTAINLY SEE, I
HOPE FROM WHAT I'VE TALKED ABOUT
SO FAR, THAT GENOMIC MEDICINE IS
REALLY CHANGING MEDICAL
PRACTICE, BECAUSE WHAT WE'RE
TALKING ABOUT HERE IS CERTAINLY
DIFFERENT THEN WHEN I WENT
THROUGH MED SCHOOL.
WE DIDN'T DO ANY OF THIS KIND OF
TESTING AT THAT TIME.
I PREDICT THAT REALLY IN THE
NEXT TEN YEARS WE'RE LIKELY TO
HAVE GENETIC TESTS THAT PREDICT
YOUR SUSCEPTIBILITY TO MAYBE A
DOZEN COMMON CONDITIONS, BUT THE
PROBLEM WITH ALL THESE COMMON
CONDITIONS, LIKE HEART DISEASE,
DIABETES, ARTHRITIS,
OSTEOPOROSIS, THESE ARE ALL
DISEASES THAT HAVE A GENETIC
COMPONENT, BUT THEY'RE WHAT WE
CALL MULTIFACTORIAL DISEASES.

A slide reads "Genomic Medicine is changing medical practice. By 2010: (there will be) predictive genetic tests for a dozen common conditions; people will learn individual susceptibilities; (people will) take steps to reduce risks."

June says THEY HAVE A GENETIC COMPONENT,
BUT THEY ALSO HAVE A HUGE
INFLUENCE OF THE ENVIRONMENT AND
OTHER FACTORS THAT CONTRIBUTE.
SO, I THINK THAT YOU'RE GOING TO
BE OFFERED THESE KIND OF TESTS.
YOU MAYBE ABLE TO LEARN ABOUT
YOUR SUSCEPTIBILITIES.
YOU MAYBE ABLE TO TAKE RISKS TO
PREVENT THESE DISEASES, BUT IT'S
CERTAINLY NOT GOING TO BE THE
WHOLE ANSWER.
THE THOUGHT IS THAT WE'LL HAVE
THESE GENE CHIPS THAT YOU'LL
HAVE IN A LITTLE PLASTIC CARD IN
YOUR WALLET THAT WILL CARRY
WHAT'S CALLED YOUR... (MUMBLING)

June says WILL CARRY YOUR RISKS OF ALL
THESE DISEASES.
SO, YOU MIGHT CARRY A LITTLE
CHIP THAT SAYS YOU'RE AT
INCREASED RISK OF COLON CANCER,
ATTENTION DEFICIT DISORDER, YOU
MAY GET HIGH PRESSURE AND YOU
HAVE AN ALLERGY TO PENICILLIN.
SO YOUR DOCTOR WOULD JUST PUT
THAT IN THEIR LITTLE MACHINE AND
SAY, OKAY, LOOKS LIKE YOU BETTER
GET EXERCISING AND EAT HIGH
FIBER.
IT COULD BE THAT KIND OF THING
THAT SORT OF HAPPENS.
SOME OF YOU MAY HAVE SEEN "DATA
CELL," WHICH WAS A MOVIE ABOUT
GENETIC TESTING WHERE PEOPLE
TOOK A HAIR, AND PUT IT INTO A
LITTLE BOOTH LIKE A LITTLE ATM
MACHINE, AND WHAT THAT GAVE YOU
WAS THE PERSONALITY PROFILE OF
THE PERSON WHO'S HAIR YOU TOOK.
SO, PEOPLE DID THAT AS A
PRECURSOR TO ANY KIND OF DATING
JUST TO MAKE SURE WHO THEY WERE
GOING OUT WITH.
SO, I MEAN IT'S FASCINATING
WHAT'S POSSIBLE.
I THINK GENETICS IS LIKELY TO
CHANGE OUR LIVES BY ALLOWING US
TO KNOW ABOUT OUR HEALTH AND
DISEASE PREDISPOSITION.
IT CERTAINLY WILL SHOW THAT
WE'RE ALL MUTANTS BECAUSE WE ALL
HAVE MUTATIONS.
IT'S GOING TO SHOW HOW SIMILAR
WE ARE TO SOME PEOPLE AND HOW
DIFFERENT WE ARE IN OTHER WAYS.
IT MAY CHANGE OUR LIVES THROUGH
WHAT I CALL GENETIC
DETERMINISM.
IF YOU FIND OUT THAT YOU HAVE
THE GENE FOR SOMETHING, ARE YOU
JUST GOING TO GIVE UP AND SAY,
WELL, IF I HAVE THE GENETIC
DISPOSITION TO LUNG CANCER, I
MIGHT AS WELL SMOKE.
WHAT DIFFERENT IS IT GOING TO
MAKE?
IT'S CERTAINLY POSSIBLE THAT IT
COULD DO THAT FOR SOME PEOPLE.
IT REALLY RAISES THE ISSUE OF
NATURE VERSUS NURTURE, WHAT'S
MOST IMPORTANT ENVIRONMENT OR
GENETICS.
IT RAISES THE ISSUE USE ABOUT
ACCESS TO CARE.
ARE WE GOING TO CREATE A SECTOR
OF THE POPULATION THAT ARE
GENETICALLY DISCRIMINATED
AGAINST?
IT RAISES ISSUES OF
CONFIDENTIALITY AND PRIVACY OF
INFORMATION.
THE RIGHT TO KNOW OR NOT KNOW,
WHEN YOU HAVE THE RIGHT TO SAY
YOU DON'T WANT TO HAVE GENETIC
TESTING OR WILL YOU HAVE TO HAVE
GENETIC TESTING?
WILL YOU HAVE TO ACT IF YOU FIND
OUT ABOUT IT?
IT RAISES THE ISSUE OF INFORMED
CONSENT BECAUSE THESE ARE VERY
COMPLEX TESTS AND THE ISSUES OF
PATENTING AND LICENSING.
WE'VE TALKED ABOUT SOME OF THESE
THINGS AT THE BEGINNING, THE
ISSUES OF DISCRIMINATION, OF
SOCIAL STRATIFICATION.
WE KNOW NOW THAT MANY
PHARMACEUTICAL COMPANIES ARE
INCLUDING GENETIC TESTING IN
THEIR CLINICAL TRIALS AND THIS
CAN BE A GREAT BENEFIT TO US IN
THE FUTURE IN SOME WAYS, BECAUSE
THEY WILL BE ABLE TO DEVELOP
DRUGS THAT MATCH YOUR GENETIC
PROFILE.
SO, THEY'LL BE ABLE TO SAY IF
YOU HAVE THIS GENETIC PROFILE,
YOU WOULD TAKE DRUG "A" BECAUSE
IT WON'T GIVE YOU ANY SIDE
EFFECTS AND NOT DRUG "B,"
BECAUSE THEY'LL BE ABLE TO MATCH
YOUR GENETIC PROFILE TO THE SIDE
EFFECT PROFILE.
SO, SOME OF THESE ARE VERY
POSITIVE AND SOME OF THEM ARE
SCARY.
[Applause]

(music plays)

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Watch: June Carroll on Modern Genetics