Friendless? It may not be your fault.
Genes are likely to determine whether or not you introduce your friends to one another and facilitate their positive interaction, the study said. Those who intermingled friends from different networks ended up with a larger, stronger social circle.
The study, co-authored by James Fowler, a UCSD political science professor, UCSD graduate student Christopher Dawes and Harvard University professor Dr. Nikolas Christakis, tested the social networks of more than 90,000 teenagers, including 1,110 fraternal or identical twins.
The networks of identical twins, who share 100 percent of their genes, were drastically stronger than those of fraternal twins, who only share half of their hereditary makeup.
The study is not the first eye-opener by Christakis and Fowler, who last year published a study that said that joy is "infectious," spreading from one happy person to another.