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commercial DNA sequencing technologies, but only by laborious, manual
research- based methods. Such rearrangements are responsible for a small percent-
age of changes in the two breast cancer genes. Myriad added a panel of fi ve com-
mon rearrangements to its BRACAnalysis test, accounting for nearly half of the
total occurrence of large rearrangements in the two genes. Because large rearrange-
ments are quite rare, a woman meeting the commonly employed selection criteria
for BRACAnalysis has less than 0.5 % risk of carrying one of the large rearrange-
ment mutations. Myriad’s BRACAnalysis Rearrangement Test (BART) is an auto-
mated molecular diagnostic test in the BRACAnalysis family of products, which
detects rare, large rearrangements of the DNA in the BRCA1 and BRCA2 genes and
is performed in women with exceptionally high risk who have tested negative for
sequence mutations and the common large rearrangements already included in
Myriad’s test.
Next Generation Sequencing-Based Breast Cancer Genetic Test (NewGene
Inc) Unlike Myriad’s test, BRACAnalysis, which is PCR-based, NewGene’s assay
uses NGS technology that results in faster turnaround times and lower costs com-
pared to other technologies. This will lead to improved access to a breast cancer
genetic test with clinical use for patients. The test is based on full gene sequencing
of the BRCA1 and BRCA2 genes, so it is not targeting specifi c mutations. NewGene
uses the Roche 454 GS-FLX platform for pyrosequencing. Unlike traditional Sanger
sequencing, which involves looking at individual segments of a gene one segment
at a time and one patient at a time, pyrosequencing enables the investigation of
genes of interest in multiple patients in the same run and with multiple gene frag-
ments in the same run. Thus, NewGene can look at 20,000 fragments in one run in
contrast to 1 fragment per run allowed by Sanger sequencing-based methods.
Because each patient requires about 100 fragments to be sequenced, the increase in
the number of patients that can be investigated in a single run and the improvement
in throughput achieved by this technology, are signifi cant. Test results using this
technology can be achieved in 4 weeks.
FAST (Fiber Array Scanning Technology) This combines laser techniques with
a whiskbroom bundle of fi beroptic threads enabling accurate detection of traveling
cancer cells, at a much faster pace than current screening allows. The approach also
employs a digital microscope to further home in on the pinpointed cancer cells.
FAST works by an ethereal method called “collecting the light.” The combination
of the FAST cytometer and the digital microscope can spot 98 % of the traveling
cancer cells in a sample. And it produces a false positive fewer than three times in a
million tries – compared with a hundred false positives in a million tries for an auto-
mated digital microscope alone − the current most accurate method. FAST cytome-
ter, has been tested on blood samples from patients. The system someday could be
used alongside mammograms for better breast cancer screening.
Real Time Qualitative PCR (Real Time-qPCR) Assays) These have been used
to risk-stratify breast cancers based on biological ‘intrinsic’ subtypes and prolifera-
tion (Perreard et al. 2006 ). Realtime-qPCR is attractive for clinical use because it is
10 Personalized Therapy of Cancer