Dr. Arthur Conan Doyle and the Case of Congenital Syphilis

In 1894, Dr. Arthur Conan Doyle wrote "The Third Generation," a short story involving the transmission of congenital syphilis from generation to generation. Analysts of his writings have interpreted the pathogenetic mechanism involved in modern terms: infection of mother by father and then transplacental infection of the fetus. However, a review of the contemporary literature and the history of the concepts of congenital and "hereditary" syphilis demonstrates that the late 19th-century understanding of the process involved a Lamarckian transmission of paternal infection, via the sperm at the moment of conception. It was undoubtedly this concept that Doyle learned in medical school in the late 1870s and that provided the background to his story.