Download 14-3: Human Molecular Genetics

14-3:
Human Molecular Genetics
Objectives:
1)What is the goal of the Human Genome Project?
2)What is gene therapy?
Human DNA Analysis
Biologists search the volumes of the human genome using sequences of DNA
bases.
Testing for Alleles
Variety of genetic tests
Use labeled DNA probes
Detect the complementary base sequences found in
disease-causing alleles
Search for changes in restriction enzyme
cutting sites
Detect differences between the lengths of
normal and abnormal alleles
Testing for Alleles cont’d
DNA testing can pinpoint the exact
genetic basis of a disorder
Possible to develop more effective
treatment for individuals affected
by genetic disease
DNA Fingerprinting
All DNA is different except for identical
twins
DNA fingerprinting: analyzes sections
of DNA that have little or no known
function but vary widely from one
individual to another
DNA Fingerprinting cont’d
How DNA fingerprinting
works
A small sample of human
DNA is cut with a
restriction enzyme
Fragments are separated
by size
Using gel electrophoresis
Fragments are detected
with a DNA probe
Revealing several DNA
bands of various sizes
DNA Fingerprinting cont’d
DNA samples can be obtained from
Blood
Sperm
Hair strands with tissue at the
base
DNA Fingerprinting cont’d
Has been used in the USA since the
late 1980’s
Has helped
Convict criminals
Overturn many convictions
https://www.youtube.com/watch?v=
XXQP_67B5yw
The Human Genome Project
1990: Scientists in USA and other
countries began the Human
Genome Project
The Human Genome Project is an
ongoing effort to analyze the
human DNA sequence
June 2000: Scientists announced
that a working copy of the human
genome was essentially complete
Rapid Sequencing
1)Determine the sequence of bases in widely separated regions of DNA
a) Used as markers
i) Made it possible to locate and return to specific locations in the genome
Rapid Sequencing cont’d
“Shotgun sequencing”: cutting
DNA into random fragments and
then determining the sequence of
bases in each fragment
Computers
Found areas of overlap between
the fragments
Put the fragments together by
linking the overlapping areas
Aligned the fragments relative to
the known markers on each
chromosome
Searching for Genes
Only a small part of a human DNA molecule is made up of genes.
Continue to search for genes in many ways
Research groups around the world
Analyzing the huge amount of information in the DNA sequence
Looking for genes that may provide useful clues to some of the basic properties of life
A Breakthrough for Everyone
You can watch/read about the latest genome data on the internet.
Gene Therapy
Gene therapy: the process of changing the gene that causes a genetic disorder
In gene therapy, an absent or faulty gene is replaced by a normal, working gene.
The body can make the correct protein or enzyme it needs
http://www.smithsonianmag.com/science-nature/gene-therapy-in-a-new-light130742057/?no-ist
Exit Ticket
Answer the following
questions.
Use complete sentences.
You may NOT use your book. You
MAY use your notes.
This is a quiz grade.
1) What is the goal of the Human
Genome Project?
2) What is gene therapy?