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Genetic tests that claim to help parents identify their kids’ “true” talents were taken to task last week on The Los Angeles Times‘ health blog:
There’s an informational video that the Inborn Talent website urges you to watch “if you end up doing nothing else today,” because the information is “critical” and “will affect and impact both the childhood and the adulthood of your child.” It warns that, without the info the test can provide, “you may be unconsciously forcing your child to do something that he or she really dislikes doing.”
And there is a long, long funny page filled with DNA images and references to the “Drawing Gene” or “Intelligence Gene” or “Self Detoxifying Gene” as well as lots of Visa/MasterCard logos and test-ordering hyperlinks that say things like “Wow, This will be the best christmas gift for my child! I want my child’s report now.”
As genetic testing gets more popular, we’re undoubtedly going to see more and more companies springing up with these sorts of ridiculous claims. (In case anyone didn’t know, researchers have not found any genes for drawing, intelligence, detox, etc…go read Elaine’s great post with more crazy examples.) But these smart, critical responses are exactly why I’m not worried about it.
In fact, when I Google “Inborn Talent” or “Inborn Talent genetic test”, the first articles that show up are critical, such as this one from Psychology Today. It’s hard enough for companies (ie, 23andMe, DeCode) that are built on some actual science to succeed; when a company is built on bullshit, its reputation will quickly plummet, and ultimately it will fail.
For more than three decades, the first-line test for spotting genetic disorders in young children has been a basic laboratory assay in which a technician analyzes a toddler’s chromosomes under the microscope for unusual structural rearrangements. About four years ago, a new technology based on fluorescent probes hit the scene and, in short order, became the default assay for most testing labs.
But some insurance companies have resisted paying for the newer tests, called chromosomal microarrays, because they are more expensive than older techniques. This delay in technological uptake could be keeping many children from receiving crucial early treatment for their conditions. Now, an expert group is calling on large medical associations to adopt microarrays as the preferred genetic tests for children with unexplained autism, developmental delays or other birth defects.
Traditional karyotyping techniques are still the best choice for conditions such as Down’s syndrome that are caused by gross chromosomal abnormalities and are easily recognized by clinicians. But most developmental disorders show a range of symptoms and can arise from more subtle genetic glitches, such as microscopic DNA deletions or duplications. That’s where the much more sensitive microarrays come in.
…read the rest of my latest in Nature Medicine
Earlier this year, I wrote about a group of scientists who are analyzing canine DNA to learn more about human psychiatric diseases. I’m happy to report that other researchers are using genetic tools to help abused dogs.
Last year, police in seven states took down a large dog-fighting ring, which included some 400 animals. After running DNA tests, the investigators discovered that most of the dogs were related — compelling evidence that their owners acquired them from the same sources and were involved in the same crimes.
That large collection of DNA (stored at the University of California, Davis) will help authorities in future cases, according to a piece in the New York Times:
“There is definitely a C.S.I. effect,” said Melinda Merck [a veterinarian for the A.S.P.C.A.]. “Juries want to know that if you have evidence you’ve run every possible test. The DNA is just one more tool in our kit that can bolster our cases.” She added, “I do think it’s something that is going to make the dog-fighting world very nervous.”
…The database may also prove useful in forensic investigations of blood samples found at a dog-fighting site, allowing them to establish the presence of a particular dog.
“One of the challenges in a lot of these fighting pits is that the losing dogs are often executed and dumped along the side of the road somewhere,” said [A.S.P.C.A. investigator] Tim Rickey. “This database may provide a useful tool for tracking down where the animal was bred, and maybe the owner.”
Some sobering news on the cancer treatment front: ‘targeted’ cancer therapies — which go after specific genetic mutations carried by tumors — don’t work in all types of tissue.
As researchers reported this week at a cancer conference in Chicago, a drug (PLX4032) that had worked wonders on reversing mutations in melanoma had no effect on the same mutation in colon cancer.
The results are frustrating, of course, but also fascinating, as Andrew Pollack reports nicely in the NYTimes:
Read the rest of this entry »
How long does a fruit fly sleep? That depends on its genetic make-up, according to research presented this weekend at a meeting of the Genetics Society of America in Boston, Massachusetts.
Researchers identified nearly 1,000 genes in which certain single-letter changes in DNA, called SNPs (for single nucleotide polymorphisms), are associated with the length of sleep.
This preliminary study is the first to come out of the Drosophila Genetic Reference Panel project, a catalogue of variations across the complete genomes of 192 inbred lines of the fruit fly Drosophila melanogaster.
So far, the researchers have deposited raw sequence data from 152 lines in a freely available database, spurring roughly 50 other groups to begin genome-wide association (GWA) studies, which compare the SNPs of flies that show various complex behaviours.
“Once all of the data are out, there will be an army of people who will immediately go after it,” says Charles Langley, a population geneticist at the University of California, Davis, who was not involved in the latest study.
…read the rest of my article at Nature News
The hunt for disease-linked genes gets a lot of attention. What a lot of people don’t realize, though, is that scientists are really looking for ‘functional’ genetic variants — those that do something important. A gene is potentially important if it a) codes for proteins, and/or b) is expressed in a body tissue that makes sense for the disease.
People searching for genes related to brain diseases, for instance, want to know which genes are actually expressed in the human brain. Now, thanks to the Allen Human Brain Atlas, they have a complete reference guide. From ScienceInsider:
The Allen Institute for Brain Science has launched its map of gene expression in the human brain. The institute, started in 2003 with $100 million in seed money from Microsoft co-founder Paul Allen, hopes the atlas will become a valuable resource for scientists studying brain function and disease.
The open access Allen Human Brain Atlas combines four data sets: anatomical images of the human brain obtained by MRI scans (to show gross anatomy), diffusion tensor imaging (which reveals the fiber tracts connecting different brain regions), histology (to show cellular level anatomy), and gene expression data. The result, scientists hope, will provide the most detailed look yet at which genes are active in which parts of the human brain.
The human brain atlas follows the mouse brain atlas released in 2006. A monkey brain atlas is currently in the works.
If the method can be validated in a larger and more diverse sample, it may lead to a useful diagnostic test, researchers say.
The current standard for autism diagnosis, a thorough behavioral assessment, has several disadvantages, notes lead investigator Valerie Hu, professor of biochemistry and molecular biology at George Washington University. For instance, children may not show the full extent of their behavioral oddities on the test day, and their behavior may change over time.
“We’re aiming for a more objective, molecular diagnosis, if possible,” Hu says. “This is not it, but it’s a start.”
The 5,000-plus teenagers starting college at Berkeley this fall have been asked to send in a cheek swab for DNA testing of three genes related to alcohol metabolism. It’s completely voluntary, but nevertheless has angered some watchdog groups. From the San Francisco Chronicle:
Berkeley officials said the university has followed appropriate privacy and consent procedures and has no intent to changes its plans.
But the Center for Genetics and Society, a Berkeley public interest organization, and the Council for Responsible Genetics, which is based in Cambridge, Mass., say the project disregards the potential harmful use of the information.
“To be so cavalier about using genetic testing in this way without appropriate safeguards is really astonishing and a very large disservice to the students they’re supposed to be educating,” said Jeremy Gruber, president of the Council for Responsible Genetics, which sent a letter to university officials Thursday criticizing the project.
…What do you think?
A 'DNA spider'
A very cool bit of technology came out this week: scientists created ultra-tiny molecular machines that use DNA as a scaffold. Theoretically, these machines could move or manipulate molecules in a cell, or even produce drugs that target specific tissues.
From The Scientist:
They have constructed DNA-based robots that can walk along a specific path unaided or collect various nanoparticles along an assembly line, according to two studies published this week in Nature.
“This has the feel to me of the beginning of a technology revolution,” said Andrew Ellington, an evolutionary engineer at the University of Texas at Austin and the vice president of the International Society for Nanoscale Science, Computation and Engineering, who was not involved in the research. “This work will absolutely pave the way for how you build molecular robots.”
The robots built in one study are a type of DNA walker, called a molecular “spider.” They are minute, mobile molecules that move along a flat surface made out of folded DNA, known as DNA origami, binding to and unbinding from the surface as they go.
…Read more about the usefulness of these tiny ‘bots
A lot of people who read this blog are scientists or science writers. And most in that group are probably intimately familiar with the thorny ethical and fascinating scientific issues revolving around personal genomics.
But my other readers — my family, friends, or random Googlers — may only have a vague understanding of what personal genomics is, let alone what its importance may be for their lives. So, for this group, I must highly recommend a post on the personal genomics landscape by Dan Vorhaus, a lawyer who specializes in genomic technology. It lays out in clear, layman’s English the various ways that genetic testing is being used, and how that might change in the future. Here’s a snippet:
Genomic researchers with novel questions will continue to require novel, and increasingly participatory, research models. Clinical practice will grow and is likely to become simultaneously more specialized (e.g., increasing availability of genetic diagnostic tests) and more generalized (e.g., incorporation of whole-genome sequences into medical records as a default). Consumer personal genomics will go wherever the entrepreneurial imagination can take it and regulatory bodies permit it, leading to splintering and further blurring between its boundaries with other categories.
