Source- Time.com 

11/20/07

Stem Cell Breakthrough

In the journal Cell, scientist Shinya Yamanaka of Kyoto University has successfully developed human embryonic stem cells from cheek cells taken from a middle-aged woman. Another researcher, James Thomson of University of Wisconsin, was also able to achieve the same results with foreskin cells from a newborn baby. Both studies circumvent the need for either eggs or embryos to set the cells' clock back. "I think this is the future of stem cell research," says Dr. John Gearhart, the biologist who first discovered human fetal embryonic stem cells. "It's absolutely terrific."

The techniques involve reprogramming adult cells using viruses to deliver the time-reversing genes. Although the method is not safe for clinical use yet, it is the first step of a promising cell manipulation without the controversial issues of fetal embryonic stem cells.

Source- ScienceNowDaileyNews 

11/5/07

Do You Have the Gene for Thick Hair?

Do you ever wonder why some people have thick straight black hair, while others have curly blond or red hair? Through the International HapMap Project, a catalog of human genetic variation, scientists found a single genetic variant that may explain why East Asians have thicker hair fibers than other people.

Geneticists at the University of Tokyo and other research centers in Japan, Thailand, and Indonesia found that East Asian hair fibers are about 50% larger than that of Europeans and about 30% larger than that of Africans. Their studies were based on genes known to be involved in hair development in mouse studies and rare inherited human diseases. A variant in a gene called EDAR was present in 88% of the Japanese and Chinese groups, and 0% in the Nigerian and Europeans groups. 

The EDAR gene codes for ectodysplasin A receptor, which is involved in the molecular pathway that signals hair precursor cells to become a follicle.  According to Ryosuke Kimura, one of the scientists involved in the study, the EDAR allele could be used as a marker for East Asian ancestry.

In addition, researchers in Iceland and the Netherlands have discovered new genes that are involved in eye and hair color, and freckles in Europeans.  All these studies are published in Nature Genetics journal. Last week, researchers reported that some Neandertals were redheads, basing their findings on a known gene for red hair.

These studies are useful in crime investigations, in genetic anthropology and in tracing ancestry.

Source- Yahoo Biotechnology News 

8/29/07

The Genome of Wine Grape Decoded

A study deciphering the genome of grapes from wine was published in the prestigious journal Nature by scientists from Italy and France.

The discovery will help scientists improve flavor as well as resistance against many diseases. The studies were done on Vitis vinifera species which Pinot Noir wine is made from. Many genes have contributed to aroma in this particular species than any other sequenced plant.

The scientists discovered that Vitis vinifera had large "families" of genes  which affected the aroma of wine. The study also found the gene responsible for anti-oxidation properties in red wine. Anti-oxidants are associated with many health benefits such as anti-viral agents and anti-aging. Furthermore, a current study is involved in isolating a gene that would increase the grape's resistance to oidium, a common form of mildew that affects Pinot Noir.

Source- Nature Publishing Group

5/25/07

What is Epigenetics?

Epigenetics is defined as the study of heritable changes in
gene expression. These changes are not a result from changes in the sequence of the DNA. Gene expression means the translation of information encoded in a gene into RNA or protein.
You can check the article at:

http://www.nature.com/nature/journal/v447/n7143/pdf/447395a.pdf

Source- Reuters news

Image retrieved from www.scienceinpublic.com

3/10/07

Largest Stem Cell Clinical Study in Asia

Researches are preparing to conduct a stem cell clinical trial in 2008 to help 400 patients with spinal cord injuries in several cities in Asia- Hong Kong, mainland China and Taiwan.

Stem cells will be taken from umbilical cord blood and will be injected into the spinal cords of the patients. Lithium will also be given to the patients to help stimulate cell regeneration. The stem cells are extracted from matching umbilical cord blood taken from public blood banks. The procedure should help patients grow new nerve fibers and would allow the new fibers to reconnect with other parts of the spinal cord.

According to Dr. Young, a scientist at Rutgers in New Jersey, the main outcome measure will be neurological motor and sensory scores such as sensation- touch, pain and also strength of several standardized muscles.

Source- Science News Online

1/22/07

Hens Laying Golden Eggs in Medicine?

In the past several years, scientists have engineered cows, sheep and other mammals to produce protein drugs.  The drawback was that these animals are large and take years to mature enough to produce the proteins of interest. In addition, since these animals are mammals, the large amounts of drugs produced make them toxic to their cells. 

Scottish scientists successfully engineered hens to produce useful drugs in their eggs and pass on this characteristic to their offspring.  The team worked with two synthetic genes that code for the antibody miR24, which has shown promise against melanoma, and protein interferon-beta-1a, which is used to treat multiple sclerosis. The scientists used viruses to transport both genes into the cells of chick embryos.  When the eggs hatched, the male chicks that carried the altered gene were later bred with normal hens.  Half the female offspring laid eggs containing both protein drugs in their whites.  The researchers reported their findings in the Proceedings of the National Academy of Sciences journal.