An international team of researchers led by King's College London has identified genetic factors that may make some individuals more or less sensitive to the environments they experience. The ...

From uncanny coincidences to shared biology, we asked the experts to explain the real forces behind the phenomenon. Twins sit near Lake Geneva in Lausanne, Switzerland. Studies suggest that the ...

Every August for the past 43 years, Twinsburg, Ohio, has hosted the biggest gathering of twins in the world. Two decades ago, organizers added an attraction to the lineup of parade, talent show and ...