genetic picture. Twin studies generally compare the concordance for a disease or other trait within monozygotic twin pairs, who share 100% of their DNA, versus concordance within dizygotic twin pairs, who share on average 50% of their DNA. In a recent article in the American Journal of Psychiatry, a Swedish team of researchers led by Paul Lichtenstein studied 7,982 twin pairs. They found a heritability of 80% for autism spectrum disorders, but also found substantial sharing of genetic risk factors among autism, attention deficit hyperactivity disorder, developmental coordination disorder, tic disorders, and learning disorders.

In another recent article in the American Journal of Psychiatry, Marina Bornovalova and her University of Minnesota colleagues studied 1,069 pairs of 11-year-old twins and their biological parents. They found that parent-child resemblance was accountedIf you've been following VC news since the Wii was released, you might still remember that the ESRB rated a few titles before the Wii was even on store shelves. Games such as Super Mario RPG, Kirby's Dream Land 3 and more were all rated back in 2006.

About mid-2007 some of these games were mysteriously removed - Super Mario RPG, Kirby's Dream Land 3, Zombies Ate My Neighbors and Duck Hunt were all rated for VC one day and were gone the next. Super Mario RPG and Kirby's Dream Land 3 have of course since been rerated and actually released on the VC.

Yesterday the ESRB decided to remove more games which have been rated since the Wii came out - Aerofighters Assault, Beetle Adventure Racing, Hagane: The Final