Good-Cholesterol Gene Isolated

After a four-decade search, scientists have identified a gene that regulates the body's level of so-called good cholesterol, an advance that someday could lead to a new way to treat one of the most common causes of heart disease.

Flaws in the gene, known as ABC1, prevent the production of a protein that the body needs to rinse excess bad cholesterol and other fats out of cells and the bloodstream.

The gene was discovered by researchers looking for the cause of Tangier disease, an extremely rare inherited illness in which the body produces virtually none of the good cholesterol, HDL. Without it, the level of the bad cholesterol, LDL, and other fats that contribute to heart attacks and clogged arteries rise unchecked.

Scientists not involved in the studies said the discovery was a significant advance in heart disease research because millions of people with cardiovascular problems have lower-than-normal HDL levels.

As many as 10 labs were looking for ABC1. It was isolated in separate studies by two sets of scientists in Germany and one in Canada. Their results appear in the August issue of Nature Genetics.

A group headed by Michael Hayden of the University of British Columbia, lead author of one of the studies, determined that ABC1 is responsible for making a protein essential to both HDL formation and the process of unloading fats from cells and the blood.

Scientists Manufacture a Flu Virus

Researchers have created a flu virus in the laboratory by combining the genetic pieces of an existing flu bug -- work they said could lead to a new type of vaccine.

Yoshihiro Kawaoka of the University of Wisconsin's School of Veterinary Medicine said he and his colleagues were able to make a flu virus that precisely duplicated a virus that was isolated in 1933 and is now used commonly in influenza research.

A report on the research was being published today in the Proceedings of the National Academy of Sciences.

Kawaoka said the importance of making a flu virus is the understanding gained about the inner workings of one of humankind's most troublesome pathogens.

To make the virus, the researchers removed and separated the eight components in the genetic makeup of a flu virus called WSN. These components are called plasmids. The flu plasmids were mixed with nine plasmids from other sources and then added to a laboratory dish containing about a million living cells. The plasmids invaded the cells in random combinations. In about one cell out of every 1,000, the plasmids combined to form the WSN flu virus.

To prove that the virus was alive, said Kawaoka, the team allowed it to make a new generation of virus that then was used to infect a new batch of cells.

The technique will allow researchers to manipulate the plasmids in order to create live viruses that could be used for flu vaccines, he said.