Peter Costello, Australia's treasurer since 1996, is the great-great-grandson of Patrick Costello, a 19th-century politician from Melbourne convicted of rigging an election. Though Peter is hesitant to talk about it, they share at least two things in common: a surname and a smirk.
"That's gorgeous!" says Professor Agnes Bankier, head of Genetic Health Services Victoria, when asked about the persistence of the smirk. Yet she can't conclusively say that it is purely a genetic quirk.Peter's brother Tim has admitted that he too inherited the self-satisfied expression.
Speaking on the telephone from Los Angeles, he revealed that his father did not smirk. Adding to the enigma of the expression, Tim said he had it when he was young, while Peter developed it over time.
"In fact, when I was a young man, I did look like that, so I think it was a genetic trait," he said. "When I was about 20, there are pictures of me with that smirk. The smirk came out in the early days with me and later days with Peter, so DNA is cruel." [Link]