This study is of significance to me personally because my father was born and raised in New Zealand, and I spent a lot of my youth there getting to know a number of native islanders. These natives - Maoris - traditionally wore feather cloaks - "kakahu" - but little was known about the origins of the feathers which comprised these cloaks until this study. This study showed that almost 99% of the cloaks were constructed using feathers from North Island brown [kiwi birds]. Molecular sexing of nuclear DNA recovered from 92 feather cloak samples also revealed that the sex ratio of birds deviated from the 1:1 ratio observed in reference populations."
For me, this was an interesting article to read given my heritage and what we have my been all semester in this class. In contrast to the previous study I posted, this one is less technical (at least in its presentation) and articulates its findings in terms that most people can understand and thus its significance is manifest.
http://mbe.oxfordjournals.org/content/28/10/2741
Saturday, December 3, 2011
Study Investigates Y-Chromosome of Geographically Defined Population
While this article is a bit technical, it serves as an example of the kind of studies molecular anthropologists produce on a regular basis. This study investigates the Y-Chromosome Haplogroup O of East Asians in order to "determine the phylogenic position of recently defined markers...in the background of Haplogroup O." This study represents one of the 'smaller' scale studies that help lead anthropologists to bigger conclusions. In this case, it redefined the positions of markers on the Y-Chromosome among East Asians.
http://www.nature.com/ejhg/journal/v19/n9/full/ejhg201164a.html
http://www.nature.com/ejhg/journal/v19/n9/full/ejhg201164a.html
The molecular clock runs more slowly in man than in apes and monkeys
An article from 1987 found - using surprising advanced technology for the era - that humans evolve slower than chimps and other apes. At the time, it was thought that the "molecular clock" (i.e. the rate at which molecular in species mutated and evolved) was the same across all species within a particular taxonomic group; this study, published in Nature magazine, proved otherwise. Check out the link below to see the study in detail - seeing it up close and in person gives one a better sense of the importance of this study's findings. Its finding raised a number of question that still intrigue scholars of molecular anthropology today, such as "Why did the Neanderthals die out, while Homo-Sapiens (modern humans) continued to thrive? Did we evolve faster than them, or did we have different modes of thinking that allowed us to succeed where our closest ancestors failed?" One can imagine how this study would have lead directly to such inquiries.
http://www.nature.com/nature/journal/v326/n6108/abs/326093a0.html
http://www.nature.com/nature/journal/v326/n6108/abs/326093a0.html
Thursday, December 1, 2011
While Genome Sequencing Speed Increases and Cost Drops, Transmitting Data Holds Them Back
BGI, based in China, can sequence the equivalent of 2,000 human genomes per day. While sequencing is faster and cheaper than ever, there is so much data that is cannot transmit results to clients over the internet because it takes too long- often they use computer disks and FedEx. The field of genomics is in a 'data deluge,' where it costs more to transmit and analyze the genome then to sequence it. The cost of sequencing a human genome dropped to $10,500 from $8.9 million in 2007. While this is a decline factor of 8-- over 4 years, computing costs only dropped by a factor of about 4 in that same time. Few human genomes are being sequenced for individual use, while the majority are part of large-scale genome studies such as searching for the cause of cancer. The federal online archives of raw sequencing data have been taking the majority of the hit, reaching 300 trillion DNA bases, about 700 trillion bytes of computer memory, since the beginning of 2011. The federal offices were considering shutting the archive due to budget constraints, but will now stay open at the charge of big sequencing projects. Meanwhile, the Human Microbiome Project is sequencing the microbial populations in the human digestive tract, and has produced a million times as much sequencing data as a single human genome. Scientists admit that they are not even sure exactly what to do with all of the data.
Some scientists are looking to Google to help solve the problem, as they have the capacity to do all of genomics in a day. Google's venture capital sector has recently investing in bioinformatics company. Researchers are storing all of the raw data in the hopes that new technology will be produced to help analyze it, but until that time they will continue amassing unmanageable amounts of data with only hope that the processing solution will come soon.
Article: http://www.nytimes.com/2011/12/01/business/dna-sequencing-caught-in-deluge-of-data.html?_r=1
First Gene to be Linked with Herpes-Related Cold Sores
Today it was released that researchers from the University of Utah and University of Massachusetts identified the first gene related to Herpes cold sores found in the human genome. Herpes is an infection caused by herpes simplex virus type 1 that affects more than 70% of the US population. Once infected, HSV-1 never leaves the body, and lies dormant until reactivated. Among infected HSV-1 people, the reactivation and outbreak of cold sores is random and occurs for unknown reasons.
Scientists today believe there are three contributing factors to the reactivation of HSV-1: the virus itself, genetic susceptibility, and environmental factors. The goal of the this team was to identify the gene that could link itself to the frequency of reactivation of the cold sore.
John Kriesel, M.D., who lead the study, said that his team used SNP genotyping to identify DNA sequence variations among infected and uninfected participants. They then used different methods to identify a genetic association between the DNA variations and frequent cold sore outbreaks.
They found that a gene called C21orf91 was associated with HSL susceptibility, and identified 5 major variations of this gene, 2 of which seemed to protect against the virus, and 2 of which seemed to increase the likelihood of having frequent outbreaks.
While there is currently no cure or preventative measures for HSV-1, this data could potentially help develop drugs that affect the cold sore frequency.
Article: http://www.medicalnewstoday.com/releases/238488.php
Scientists today believe there are three contributing factors to the reactivation of HSV-1: the virus itself, genetic susceptibility, and environmental factors. The goal of the this team was to identify the gene that could link itself to the frequency of reactivation of the cold sore.
John Kriesel, M.D., who lead the study, said that his team used SNP genotyping to identify DNA sequence variations among infected and uninfected participants. They then used different methods to identify a genetic association between the DNA variations and frequent cold sore outbreaks.
They found that a gene called C21orf91 was associated with HSL susceptibility, and identified 5 major variations of this gene, 2 of which seemed to protect against the virus, and 2 of which seemed to increase the likelihood of having frequent outbreaks.
While there is currently no cure or preventative measures for HSV-1, this data could potentially help develop drugs that affect the cold sore frequency.
Article: http://www.medicalnewstoday.com/releases/238488.php
Scientists Use Gene Therapy to Prevent Aids in Mice
Nobel Laureate David Baltimore of the California Institute of Technology published a study on Wednesday describing how by inserting a gene into the leg muscles of mice (who were bred to be susceptible to HIV), the mice created antibodies that were able to protect them against exposure to HIV. While 1 nanogram of the virus is usually enough to infect a mouse with HIV, these mice were administered up to 100 nanograms of the virus, significantly more than a human would ever experience, and still withstand it. This technique was first used in 2009 to protect monkeys against the spread of a similar disease as HIV, yet only transmittable to monkeys.
Testing will commence soon on humans soon. If there proves to be no dangerous side-effects, as there is no cure yet for AIDs, this preventative gene therapy may be the new way to at least prevent the spread. While scientists have found many effective antibodies against different mutations of the AIDs virus, they have so far not been able to make the human body produce them. So while the potential gene therapy solution seems promising, scientists must proceed with caution. With gene therapy, once the gene is inserted, if there are complications there is no way to switch it off.
Article: http://www.medicalnewstoday.com/articles/238493.php
Testing will commence soon on humans soon. If there proves to be no dangerous side-effects, as there is no cure yet for AIDs, this preventative gene therapy may be the new way to at least prevent the spread. While scientists have found many effective antibodies against different mutations of the AIDs virus, they have so far not been able to make the human body produce them. So while the potential gene therapy solution seems promising, scientists must proceed with caution. With gene therapy, once the gene is inserted, if there are complications there is no way to switch it off.
Article: http://www.medicalnewstoday.com/articles/238493.php
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