Transcript Huntingtons Disease Powerpoint

THE
INHERITANCE
OF DOMINANT
GENES
.
Bob Dylan wrote some of
the most important songs
of the 60’s and is
considered “the most
important lyrist of this era
Robert Zimmerman
grew up in Minnesota
in the 50’.
He changed his name to
Bob Dylan
But in 1960 he moved
to New York City and
began writing and sing
folk songs
He continued to
have hit songs
into the 70’s and
80’s
Such as - The
Times They Are
A-Changin’
In 1988 he was
inducted into the
Rock and Roll
Hall of Fame, for
songs such as
“Like a Rolling
Stone”
In 1998
his album
received
a
Grammy
for album
of the
year
In 2001, Bob Dylan
received an Academy
Award for his song
“Things Have Changed”
from the movie
Wonder Boys.
His music
and writing
has
influenced
generations
of
musicians
including:
The song “Mr.. Jones” by the Counting
Crows draws from the Dylan song
“Ballad of a Thin Man”
But why did Bob Dylan go to
New York City?
He went to
visit his idol Woody Guthrie
who was dying
in the hospital
Dylan’s first
album had
“Song for
Woody
Woody Guthrie
was one of the
“most influential
cultural figures”
of the Depression
Era.
He wrote over one
thousand songs
between 1932 and
1952.
Woody Guthrie sang about
repressed people, such as the
Okies coming to California
during the Depression. He and
John Stienbeck’s book “Grapes
of Wrath” greatly influenced
how farm workers were later
treated
Guthrie is
remembered for
many songs, but
the one most
often sung by
every camper
and scout is ...
Woody
Guthrie’s
other
legacy to
music is all
the other
song
writers he
has
influenced
such as:
Springsteen
Baez
Woody Guthrie
was born in
1912 to
Charley and
Nora Guthrie.
He had one
sister, Clara,
who died in a
mysterious
house fire.
CHARLEY
WOODY
NORA
In 1973
Woody
Guthrie died
of
Huntington’s
Disease after
fifteen years
of hospitalzation.
Huntington’s Disease results from
the deterioration of nerves such as
those in the center of the
Huntington’s brain on the right
Woody had three children with his last wife.
Joady, Nora and Arlo
WOODY
Joady
Arlo
Nora
Woody
Guthrie
spent the last
fifteen years
of his life in
mental
institutions
and
hospitals.
His children
were with
him at the
time of his
death in
1973.
We’ll concentrate on
the middle child,
Arlo. Arlo also
became a song writer.
He’s most famous
song was actually
made into a movie
Woody- Hh
H
h
h
Hh
hh
h
Hh
hh
Actually, Woody’s married
life was much more complex
and by looking at the
complete pedigree we can
see how a dominant gene,
such as Huntington’s
Disease, is inherited.
Both Gwen and Sue inherited the
Huntington gene and died form the
affliction.
In 1979 Nancy Wexler
began studying a
village in Venezuela
where Huntington’s
Disease was common
rather than rare.
Through her work with
thousands of blood
sample, she was able to
identify the location of
the gene that causes
Huntington’s Disease.
Like
Arlo
Guthrie,
Nancy
Wexler
had a
parent
who
died
from Huntington’s Disease.
Through Wexler’s
research, the gene
causing
Huntington’s
Disease was
located at the tip
of chromosome 4.
Soon after discovering the
location, six universities
working under the direction
of Nancy Wexler, identified
the sequence of the A’s, G’s,
C’s, and T’s. The University
of California, Irvine was the
major researcher in
identifying the sequence of
the Huntington”s Disease
gene.
The mutation that causes Huntington’s Disease
is a repeating of the three bases C,A,G in the
gene. The more often the repeat of the CAG
sequence the more likely it is to contract the
disease and the earlier the disease starts.
A–C – C–G –T–C– G –A–T–C –A–G –A–A–C–T–T–
A–C – C–G –T–C– G –A–T–C –A–G –A–A–C–T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–A–A–
C–T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–A–A–C–T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–A–A– C –T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–C –A– G –A–A–C –T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–C –A– G –C–A–G–A–A–C –T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–C –A– G –C–A–G–C –A–G–A–A–C –T–
T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–C –A– G –C–A–G–C –A–G–C –A–G–A–
A–C–T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–C –A– G –C–A–G–C –A–G–C –A–G–C –
A–G–A–A–C –T–T–
A–C – C–G –T–C– G –A–T–C –A–G–C –A– G–C –A–
G–C –A–G–C –A– G –C–A–G–C –A–G–C –A–G–C –
A–G– C –A–G –A–A–C –T–T–
Adding multiple copies of the C – A – G
codon, changes the amino acid sequence
in the copy.
The
Huntington
gene has a
section
where three
bases repeat
over and
over, causing
a protein
with a
section of
repeating
amino acids.
The reason Huntington’s Disease symptoms
do not appear until late in life is that the
incorrect protein takes time to builds up in
the nerve cells, until the cell eventually dies.
The repeating CAG sequence is
responsible for other genetic conditions
Soon after the
location and
sequence of the gene
were identified, a
genetic test was
developed to
determine if the
Huntington’s
mutation is present.
Even though she was
instrumental in
developing the
genetic test for the
Huntington’s gene,
Dr. Wexler will not
reveal if she has had
the test.
Neither has Arlo
Guthrie
We ended with the
local University,
UCI, where the
sequence of the gene
was discovered
Arial view of
University of California,
Irvine
Medical Science Building at UCI
From Nancy
Wexler, who
identified
the location
of the gene
on
chromosome
From Arlo
Guthrie
who
inherited
two
recessive
normal
genes.
From Woody Guthrie who died because he
was heterozygous for the Huntington gene.
From
Bob
Dylan
who
went to
New
York to
visit
Woody
in the
hospital.
And back to
me and my
first date in
the car to see
Bob Dylan at
the Hollywood
Bowl.
All
because
Huntington’s
All because
Disease is inherited as a
dominant trait:
1) What was Woody Guthrie's genotype for Huntington’s Disease.
2) What is the genotype of Arlo Guthrie.
3) Construct the Punnett square for Nancy Wexler.
4) What is the probability that Nancy Wexler does have Huntington’s
Disease?
5) Construct the pedigree for Woody Guthrie. (He had two sisters.)
6) What is the probability that his little sister, who died in a
“mysterious” fire, would have had Huntington’s Disease if she had
lived?
So we come back to the beginning, Nancy
Wexler identified the location of the gene
that cause the Huntington’s Disease that
Arlo Guthrie did not had but that killed
his dad, Woody Guthrie, who Bob Dylan
went to New York to visit where he was
discovered and went on to become one of
the most influential song writers of the
20th Century because of the Huntington
Disease gene.