Major progress in health through technology_美文

Major progress in health through technology

A patient with an arrhythmia, or irregular heartbeat, might one day be able to have a normal heartbeat with the injection of a single gene. The experimental gene would help to create a natural heart pacemaker. This would end the need for placing an electronic device in a person’s chest to control the heartbeat.

Researchers in California created what they are calling “biological pacemaker cells” by adding a single gene to a virus. They then injected the engineered virus into the hearts of guinea pigs. The animals had been bred to suffer from arrhythmia.

The gene caused the creation of an exact copy of the sino-atrial node in the heart’s upper right chamber. Other studies have shown that this node helps to keep the heart beating normally. The gene changed heart muscle cells -- called cardiomyocytes -- into natural pacemaker cells.

Eduardo Marban is director of the Cedars-Sinai Health Institute in Los Angeles. He says the node, called S-A-N, makes up just 10,000 cells among the ten billion heart muscle cells. He says the tissue made by the inserted gene looks almost like the structure it replaces.

“If we were to give scientists who are specialized in this area the data to look at it then compare it to a genuine pacemaker cell -- which, as I said, are exceedingly rare -- to the ones we created by putting a gene into an ordinary heart cell, it’d be, they’d be hard-pressed to tell the difference.”