 The intention was to determine whether protein or DNA was the genetic material, but upon consultation with Max Delbrück, they determined that their results were inconclusive and could not specifically identify the newly labeled molecules as DNA.Watson never developed a constructive interaction with Kalckar, but he did accompany Kalckar to a meeting in Italy, where Watson saw Maurice Wilkins talk about his X-ray diffraction data for DNA.Watson was now certain that DNA had a definite molecular structure that could be elucidated.