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Indian Pediatr 2013;50: 619 |
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News in Brief |
Gouri Rao Passi,
Email:
[email protected]
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Can We Patent A Human Gene?
A contentious issue is being debated in the US
Supreme Court which may have wide ranging ramifications in medicine. The
judges themselves agree it is one of the most fascinating questions they
have pondered. The question is deceptively simple. Can a human gene be
patented?
The story begins in 1990 when Dr Marie-Claire King
discovered a breast cancer gene on chromosome 17 later called the BRCA
gene. A group of scientists then formed a company called Myriad Genetics
and discovered risky mutations on this gene most famously the BRCA1 and
BRCA2. The presence of mutations on these tumor suppressor genes
increases the risk of breast cancer by 5 times and ovarian cancer by 10
-30 times. Myriad Genetics promptly filed for a patent and then
developed a diagnostic test BRCA Analysis. The fallout of the patent is
that anyone needing to do the test must necessarily pay thousands of
dollars while the actual cost to the company is about $200.
In 2009, a lawsuit was initiated by the American
Civil Liberties Union and the Public Patent Foundation on behalf of 20
plaintiffs, challenging Myriad’s right to patent the BRCA1 and BRCA2
genes. Over the next few months it will be interesting to see how the
Supreme Court will decide what is being touted as "the broadest possible
question" (The Hindu 20 April 2013, The New York Times 14 April 2013).
Portable Device to Detect Infections
Scientists from Massachusetts General Hospital have
developed a hand held device which can detect bacteria including
tuberculosis in just a few hours. After DNA is extracted from the
sample, any of the target sequence that is present is amplified using a
standard procedure, then captured by polymer beads containing
complementary nucleic acid sequences and labeled with magnetic
nanoparticles with sequences that bind to other portions of the target
DNA. A miniature NMR coil incorporated into the device — which is about
the size of a standard laboratory slide — detects any TB bacterial DNA
present in the sample. Tests of the device on samples from patients
known to have TB and from healthy controls identified all positive
samples with no false positives in less than three hours.
Another paper published in The Nature
Nanotechnology, describes a similar system using ribosomal RNA (rRNA)
— already in use as a bacterial biomarker — as a target for nanoparticle
labeling. The investigators developed both a universal nucleic acid
probe that detects an rRNA region common to many bacterial species and a
set of probes that target sequences specific to 13 clinically important
pathogens, including Streptococcus pneumoniae, Escherichia
coli and methicillin-resistant Staphylococcus aureus (MRSA).
The device was sensitive enough to detect as few as one or two bacteria
in a 10 ml blood sample and to accurately estimate bacterial load.
Testing the system on blood samples from patients with known infections
accurately identified the particular bacterial species in less than two
hours and also detected two species that had not been identified with
standard culture techniques (The Hindu 6 May 2013,
http://www.sciencedaily.com 5 May 2013).
Does India Really Have More Malnutrition Than
Sub-Saharan Africa
‘Truth in numbers is an essential element in serious
intellectual discourse.’ It has long foxed experts why percentages of
malnourished and stunted children in India outstrip those in Sub-Saharan
Africa. Arvind Panagariya, Professor of Economics at the Columbia
University, USA has tried to relook the question in a special article in
the May issue of the Economic and Political Weekly. The contention of
the paper, instead, is that the current globally uniform height- and
weight-based measures of child malnutrition, which place India behind
nearly every Sub-Saharan African country, are premised on invalid
assumptions and therefore need correction. He compares health indices of
Kerala with that of Senegal and Mauritiana. Senegal, which has 4.25
times the infant mortality rate of Kerala, almost six times Kerala’s
underfive mortality, and 4.3 times Kerala’s maternal mortality ratio,
has lower rates of stunting and underweight children. It is puzzling if
you consider that female literacy rate in Kerala is 92% in sharp
contrast to 29% in Senegal and 51% in Mauritiana. The same pattern
repeats when India is compared to each of the 33 Sub-Saharan African
countries with lower per capita incomes. Several findings and arguments
show that the absence of a balanced diet alone cannot fully explain the
estimates of stunted and underweight children in India. The "gradual
catch-up" hypothesis that generations of good food will slowly improve
overall nutrition and genetic differences both, is probably at work. But
the fact that Japanese adults have remained 12 to 13 cm shorter than
their Dutch counterparts despite more than 50 years of good diet implies
that genetic differences are important and the use of same standards
globally to identify malnutrition, is flawed. Without genetic
differences, there is no empirically plausible explanation for the
significantly higher levels of malnutrition and stunting in India versus
Africa. He argues that it is imperative to develop country- or even
region-specific norms for height and weight to have a true perspective
of the complicated issue of malnutrition (Economic and Political
Weekly, 4 May 2013).
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