7th Grade Science – Article Abstract 10 – 75 Points (Note – 3 Separate Articles!)
INSTRUCTIONS: Read the articles, prepare the correct citation, and create two questions, with answers, for each article.
----------------------------------------------------------------------------------------------------------------------------The Era Of Genetically-Altered Humans Could Begin This Year. By David DiSalvo, contributor to
Forbes Magazine online, published 1.26.2015.
http://www.forbes.com/sites/daviddisalvo/2014/01/26/the-era-of-genetically-altered-humans-couldbegin-this-year/
By the middle of 2015, the prospect of altering DNA to produce a genetically-modified human could
move from science fiction to science reality. At some point between now and July, the UK parliament
is likely to vote on whether a new form of in vitro fertilization (IVF)—involving DNA from three
parents—becomes legally available to couples. If it passes, the law would be the first to allow prebirth human-DNA modification, and another door to the future will open.
The procedure involves replacing mitochondrial DNA (mtDNA) to avoid destructive cell mutations.
Mitochondria are the power plants of human cells that convert energy from food into what our cells
need to function, and they carry their own DNA apart from the nuclear DNA in our chromosomes
where most of our genetic information is stored. Only the mother passes on mtDNA to the child, and it
occasionally contains mutations that can lead to serious problems.
According to the journal Nature, an estimated 1 in 5,000-10,000 people carry mtDNA with mutations
leading to blindness, diabetes, dementia, epilepsy and several other impairments (the equivalent of
1,000 – 4,000 children born each year in the U.S.). Some of the mutations lead to fatal diseases, like
Leigh Syndrome, a rare neurological disorder that emerges in infancy and progressively destroys the
ability to think and move.
By combining normal mitochondrial DNA from a donor with the nucleus from a prospective mother’s
egg, the newborn is theoretically free from mutations that would eventually lead to one or more of
these disorders. While never tried in humans (human cell research on mtDNA has so far been
confined to the lab), researchers have successfully tested the procedure in rhesus monkeys.
Last March, the UK Human Fertilization and Embryology Authority wrapped up a lengthy study of
safety and ethical considerations and advised parliament to approve the procedure in humans.
According to New Scientist magazine, parliament is likely to vote on the procedure by July of this
year. If the procedure overcomes that hurdle, it will still take several months to pass into law, but the
initial vote will allow researchers to begin recruiting couples for the first human mtDNA replacement
trials.
The U.S. is not nearly as close to approving mtDNA replacement as the UK seems poised to do; the
U.S. Food and Drug Administration will start reviewing the data in earnest in February. Among the
concerns on the table is whether the mtDNA donor mother could be considered a true “co-parent” of
the child, and if so, can she claim parental rights?
Even though the donor would be contributing just 0.1 percent of the child’s total DNA (according to
the New Scientist report), we don’t as yet have a DNA benchmark to judge the issue. Who is to say
what percentage of a person’s DNA must come from another human to constitute biological
parenthood?
Other scientists have raised concerns about the compatibility of donor mtDNA with the host nucleus
and believe the push to legalize human trials is premature. By artificially separating mtDNA from the
1
nucleus, these researchers argue, we may be short-circuiting levels of genetic communication that
we’re only beginning to fully understand.
These are but two of many issues that this procedure will surface in the coming months. One thing is
certain: we’re rapidly moving into new and deeper waters, and chances are we’re going to need a
bigger boat.
You can find David DiSalvo on Twitter @neuronarrative and at his website, The Daily Brain. His latest
book is Brain Changer: How Harnessing Your Brain’s Power To Adapt Can Change Your Life.
1. List the title of the article, the author, where it was published, and the date it was published.
2.
3.
----------------------------------------------------------------------------------------------------------------------------Embryos Show All Animals Share Ancient Genes. By Jennifer Viegas published by Discovery
News online, December 8th, 2010. http://news.discovery.com/animals/ancient-genes-embryos.htm
The discovery helps to explain why human embryos resemble those of animals at the early stages of
life.
Human embryos resemble those of many other species because all animals carry very ancient
genes. These genes date back to the origin of cells, which are expressed during a middle phase of
embryonic development, according to two separate papers published in this week's Nature.
The findings help to explain why our embryos have a tail when they are a few weeks old and why
human embryos retain other characteristics, such as fur-like hair and fish embryo similarities, seen in
the developmental stages of other species.
"On average, the similarities will be even stronger for more closely related species," Diethard Tautz
told Discovery News.
"However, it is indeed true that even fish and human embryos go through a phase that looks very
comparable, while they are rather different before and after this," added Tautz, who co-authored one
of the papers and serves as managing director of the Max Planck Institute for Evolutionary Biology.
He and colleague Tomislav Domazet-Loso tackled the "ontogeny recapitulates phylogeny" puzzle.
This expression means that a more advanced organism, like humans, will resemble less advanced
species during it's development stages.
The researchers studied the genes of zebrafish. The scientists classified the genes according to their
evolutionary origin in the history of life and measured their contributions at different time points in the
zebrafish life cycle.
The researchers found that the oldest genes evolutionarily were expressed during a middle phase,
also known as the "phylotypic period," of the zebrafish's embryonic development.
2
"(Our) paper shows in addition the interesting effect that old animals return also to old gene
expression patterns, suggesting that they increasingly switch off the genes that have helped them to
go through adulthood," Tautz said.
For the second study, Casey Bergman, a lecturer in computational and evolutionary biology at the
University of Manchester, Pavel Tomancak and their colleagues approached the embryo similarities'
puzzle from another perspective: They measured differences in gene expression between various
species of the fruit fly Drosophila.
Again the scientists observed that development among the various species was comparable during
the middle phylotypic phase.
"Genes that are active during the middle embryonic period are involved in organizing the overall body
plan of the organism, such as the body axes and major tissues and organs," Bergman explained to
Discovery News.
He continued that the earlier and later developmental stages instead "use genes involved in utilizing
materials in the egg provided by the mother and more species specific aspects of animal form
involved in environmental adaptations."
Evolutionist Charles Darwin noticed such patterns in other species, but the two new studies show
what is happening at the genetic level. They all support what is known as the "hourglass model" of
embryogenesis.
It's dubbed that because the middle point marks the often-shared phylotypic period when the
individual's basic body plan is laid down, while the beginning and end points are more genetically
divergent and unique to the particular species.
"The similarity of animals at the center of the hourglass is shared by species in the same group of
organisms, that is, among all vertebrates (including mammals, fish and birds) or among all insects,
but not between insects and vertebrates," explained Bergman.
Human embryos at a certain stage therefore have a tail and folded neck structures that, in fish, later
turn into gills. In humans, the folded structures become our jaws. Bergman said human embryos also
possess a laryngeal nerve that travels from the brain underneath the aorta and then back to the
larynx.
"The unnecessarily long path of this nerve is shared by all vertebrates and only makes sense when
considering the origin of vertebrates is from a fish-like ancestor," he said.
"We are just very highly evolved fish!" Bergman concluded.
1. List the title of the article, the author, where it was published, and the date it was published.
2.
3.
3
Genetic test kits to hit stores amid controversy. By Sandra M. Jones, Bruce Japsen and Trine
Tsouderos, Chicago Tribune reporters 10:32 PM CDT, May 11, 2010.
www.chicagotribune.com/business/ct-biz-0512-genetic-tests-20100511,0,7466502.story
Scientists, bio-ethicists and genetic counselors worry consumers will misuse or misunderstand test
results
Coming soon to a drugstore near you, alongside the aspirin and greeting cards, will be the promise of
answers to some of life's most personal mysteries: Am I at risk for Alzheimer's disease? Or breast
cancer? Or obesity?
Starting Friday, Walgreens will begin selling Insight personal genetic testing kits, becoming the first
major retail chain in the U.S. to offer home tests that say they assess the risk of developing one of
dozens of different health conditions. CVS plans to have it in stores by August.
The product's introduction raises immediate concerns among scientists, bio-ethicists and genetic
counselors. They worry that consumers will misuse or misunderstand the results of a test so open to
interpretation it is potentially meaningless, or frightening, especially without a full medical
assessment.
On Tuesday, the Food and Drug Administration told the Tribune it is investigating the medical claims
the product's manufacturer, California-based Pathway Genomics, is making in marketing its genetic
test, which hasn't been approved by U.S. regulators.
Pathway officials say the company's home genetic test meets federal regulations and doesn't require
FDA approval.
"The tests conducted are not an in-vitro medical device and are not intended for use in diagnosis,
treatment, mitigation or cure of disease. It does provide information that allows a person to learn
about their health to make healthier lifestyle choices," said Ed MacBean, Pathway's vice president of
product management. "If the FDA contacts us, we will discuss it and address any concerns they might
have."
Drugstores already carry DNA paternity and gender prediction tests that can be done at home, and
genetic test kits are sold online by several firms. But genetic testing typically requires a visit to the
doctor's office, allowing for consultation with a health care professional.
Marketers think such kits could become as common as early pregnancy tests, helping consumers get
initial information before going to the doctor.
"We recognize that for some people, genetic responses are becoming a more important component
of managing their health care," said Jim Cohn, a spokesman for Deerfield-based Walgreens. "There
are people who want to know more about their genetic makeup, and we pride ourselves on being
convenient and accessible."
The Insight genetic test kit, priced at $20 to $30, comes with a vial and a shipping envelope. Buyers
send a sample of their saliva to a Pathway Genomics laboratory and receive their results online. The
report costs $79 to $179, depending on the type of test requested.
The kits will be appear on the shelves at about 6,000 of Walgreens' 7,500 stores nationwide.
4
Pathway Genomics Chief Executive Jim Plante said in a statement that his company is
"revolutionizing" the way people access information about their genetics. "The value of knowing how
genes play a role in our personal lives, and potentially the lives of our children, is critical for making
well-informed health and wellness decisions," he said.
Pathway screens for genetic markers of more than 70 diseases, including diabetes, prostate cancer
and cystic fibrosis. The company notes that "some markers have been researched more thoroughly
than others, but scientific knowledge advances rapidly."
It recommends buyers discuss results with a doctor or one of Pathway's genetic counselors,
particularly for complex health issues such as heart disease and cancer that have multiple causes,
including lifestyle and environmental factors, MacBean said.
Scientists question the value of home genetic testing. For most diseases, no one knows exactly why
one person gets it and another does not, said Peter Kraft, deputy director of the Program in Molecular
and Genetic Epidemiology at Harvard School of Public Health.
"The company states, everyone has the right to know the secrets hidden within their DNA," he said.
"Fair enough, but that is a lot of work. I don't think this is the way to go."
According to a paper published in The Lancet in May, a team of more than 30 researchers took a
year to analyze the results from full-genome testing of a 40-year-old man with a family history of
coronary artery disease who died suddenly. Although the amount of data they analyzed was far
greater than that of Pathway's kit, the researchers used much of the same data on genetic health
risks, disease risk and drug information.
Even then, the researchers acknowledged that the genetic information was incomplete, said Dr.
Nilesh Samani, a professor of cardiology at the University of Leicester in England who wrote a
commentary on the study.
Many of the risks have been calculated for the entire population, Samani said, but that doesn't mean
it applies neatly to any one individual because of family history, lifestyle habits or, importantly, genetic
variations.
Samani likened it to a card game in which you can only see a few cards. At first blush, you may be
holding a bad hand, but what if the cards you can't see are all aces?
"You need to know the rest to know whether it is worthwhile," Samani said. "That is a limitation. It is a
big limitation. [The companies] don't present it like this."
1. List the title of the article, the author, where it was published, and the date it was published.
2.
3.
5