Gene turns heart cells into pacemaker Self-starter A gene
inserted into ordinary heart cells transformed them into rare
"pacemaker" cells that regulate cardiac rhythm, according to
experiments carried out on lab rodents. The research is a step
toward the goal of a biological fix for irregular heartbeat,
which at present is tackled by drugs or electronic pacemakers,
its investigators write. The heart has 10 billion cells but
fewer than 10,000 of them are pacemaker cells, which generate
electrical activity that spreads to other cardiac cells, making
the organ contract rhythmically and pump blood. The work,
reported in the journal Nature Biotechology , uses a virus to
deliver a human gene called Tbx18, whose normal role is to coax
immature cells into becoming pacemaker cells. Ordinary cells
"infected" by the harmless Trojan horse were reprogrammed by Tbx
18 and became these important specialised cells. "The new cells
generated electrical impulses spontaneously and were
indistinguishable from native pacemaker cel