A family photo album can reflect how physical traits, such as blue eyes or lanky limbs, have been passed down — but a new analysis suggests that the way personality emerges across generations is far more complicated.The meta-analysis, published Sept. 2 in the journal Nature, is the largest of its kind ever attempted. The work identified over 1,200 genes linked to five personality traits: extraversion, agreeableness, conscientiousness, openness to experience and neuroticism.However, the scientists behind the study said its most important conclusion is that no single gene determines whether an individual will have a particular personality trait. Instead, thousands of genes exert tiny effects t...