Virus can be passed from parents to kids

TAMPA, Fla., March 10 (UPI) -- University of South Florida scientists say they've discovered a common herpes virus hidden in some people's chromosomes can be reactivated to infectious form.

The university's Molecular Virology Research Group said the human herpes virus 6 infects nearly 100 percent of humans during early childhood, and the infection lasts for the rest of a person's life.

Scientists, led by Professor Peter Peter Medveczky, have discovered that in some individuals, HHV-6 causes the permanent infection by inserting or "integrating" its DNA into human chromosomes, thereby protecting itself from the immune system.

The team also confirmed preliminary results by other investigators that the virus began inserting its DNA into the DNA of human sperm and egg cells long ago. As a result, they said some people -- about 1 percent of the U.S. population -- are born with the virus's DNA in every cell in their body.

The researchers say HHV-6 is the first functional virus of any type reported to be passed through the human germ line. They also said they found evidence the virus can insert its DNA specifically into telomeres -- structures at the ends of each chromosome that play key roles in aging and cancer. And they also found the chromosomally integrated HHV-6 genomes can be reactivated to an infectious form.

The study appears in the early online edition of the Proceedings of the National Academy of Sciences.