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Griffiths A.J.F., et al. Introduction to genetic analysis (8th ed., draft, 2004)(600dpi)(T)(C)(707s)_B_.djvu
Date Jun 22, 2005
opines are imported into the bacterial cells of the grow-
growing tumor and metabolized by enzymes encoded by the
bacterium's opine-utilizing genes on the Ti plasmid...
important element on the cointegrate plasmid is a selectable
marker that can be used for detecting transformed cells...
Genetic engineering in animals
Transgenic technologies are now being employed with
many animal model systems...
Perhaps the best-known plant
example is the Activator transposable-element system first
described in Zea mays (corn), which has been developed
into a transgenic cloning vector for use in many plants...
musculustransgenes inserted in
ectopic с • •-• -I locations, (a) Method of injection, (b) A
typical ectopic integrant, with multiple copies of the
recombinant transgene inserted in an array...
Consequently, virtually the only cells that survive and
proliferate are those harboring the targeted insertion (green)...
These regulatory se-
sequences lead to the expression of any immediately adja-
adjacent gene in the presence of heavy metals...
Somatic gene therapy (Figure 11-39b) attempts to
correct a disease phenotype by treating some somatic
cells in the affected person...
Gene therapy for cystic fibrosis is being attempted by in-
introducing viruses bearing the wild-type cystic fibrosis al-
lele through the nose as a spray...
Donor DNA and vector DNA are cut by the
same restriction endonuclease at specific sequences...
such cases, the method can be adapted to identify the
presence of a mutant allele or its wild-type counterpart
After transformation of an ampstets recipi-
recipient, AmpR colonies are selected, indicating successful
In the PCR process, if we assume that each cycle
takes 5 minutes, how many fold amplification would
be accomplished in 1 hour?
Is it a coincidence that the 1.5- and 1-kb fragments
together equal the 2.5-kb fragment in size?
Therefore, to investigate fur-
further, you would like to find out its mutant pheno-
A cystic fibrosis mutation in a certain pedigree is due
to a single nucleotide-pair change...
What kind of "previous mutational analyses" do you
think are being referred to?
44200_ll_p341-388 3/9/04 1:18 PM Page 387
A crucial step in genomics is to obtain a full genome
sequence, which is done by the automated sequencing of
The nature of genomics
After the development of recombinant DNA technology
in the 1970s, research laboratories typically undertook
the cloning and sequencing of "one gene at a time" (as
discussed in Chapter 11), and then only after having had
first found out something interesting about that gene
from a classic mutational analysis...
But the scale that was needed to sequence a complex
genome was, as an engineering project, far beyond the
capacity of the research community then...
Because making a complete
sequence map of a genome is such a massive undertak-
undertaking, of a sort not seen before in biology, new strategies
must be used, all based on automation...
Therefore, any given DNA se-
sequence read from a bacterial genome will come from one
unique place in that genome...
because the size of each clone was known (that is, it came
from a library containing genomic inserts of uniform
size, either the 2-kb, 100-kb, or 150-kb library), the dis-
distance between the end reads was known...
The order of the bands is not determined in this
technique, just the proportion of bands that are shared be-
between two clones...
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