Tuesday, November 01, 2005

Cell Lineage Trees Developed

Cell Lineage Trees Developed

The Weizmann Institute of Science in Israel announced that a research team has developed a method of tracing the lineage of individual cells. The researchers proved that the tiny mistakes in copying DNA which sometimes occur when a cell divides carry a history of cell division. According to the press release, “The study focused on mutations in specific, mutation-prone areas of the genome known as microsatellites. In microsatellites, a genetic 'phrase' consisting of a few nucleotides(genetic 'letters') is repeated over and over; mutations manifest themselves as additions or subtractions in length. Based on the current understanding of the mutation process in these segments, the scientists proved mathematically that microsatellites alone contain enough information to accurately plot the lineage tree for a one-billion-cell organism.” A one-month old human embryo contains a billion cells.

In the study, the team used organisms with a rare genetic defect which allows frequent and rapid mutation. (Normal cells self-correct the copying errors.) They then used a computer program to trace the cell lineage tree. The mathematical research was tested by observing the cell division in culture.

This is truly exciting news in biology. With a method of obtaining a biological history, researchers may eventually (but not soon, this is me projecting and not a scientific pronouncement by a researcher!) be able to find an accurate and highly specific genetic marker for the possibility of certain cancers or disease arising. It should also help stem cell researchers in directing differentiation. There is probably also the possibility of particular drugs or therapies being developed to correct the mutations before they replicate.

More on California Stem Cell Issues

More on California Stem Cell Issues

Monday there was an informal state legislative hearing in San Francisco on the state funded CIRM (California Institute for Regenerative Medicine) and the question of how taxpayers will get a “return on their investment.” According to the San Francisco Examiner, one proposal was for revenue sharing with state funded companies that develop successful treatment options, and one was for an agreement whereby the state can buy treatments cheaply from the companies it has funded. The first proposal could increase the interest on state bonds, costing the state another $690 million, and the second would be a loss if no treatments were developed. Another issue on the table is whether or not universities can patent and sell the results of their research, or will be obligated to give them to the CIRM and the state. The California Council on Science and Technology has recommended following the federal guidelines, which would allow universities to hold their own patents and get the commercial benefit from them. This recommendations is objected to by people who see it as breaking the promise to the voters of a return on their investment and also as decreasing the availability of stem cell treatment for the poor or uninsured. The story has also been reported in the Daily Review (and other InsideBayArea.com publications).

These are important issues to watch, since they will likely set the standard for any other states which create similar programs.