Genetic explanations of human differences became increasingly popular in the 1980s and 1990s. Unfortunately, there has been relatively little analysis of how the media portray the findings of genetic research and how this is likely to affect the public's perceptions of genetics and people's responses to those who are defined as genetically different. This study is based on a discourse analysis of articles reporting research on genetic-based differences of sex and sexual orientation that appeared in a selection of "popular" (i.e., mass circulation) science journals published between 1980 and 1997. The study uncovered a number of enduring images of genetic research and genetic differences that underlie shifts in research foci evident during this period. The article discusses the nature of these images and implicit gender and heterosexist biases and argues the case for further analysis of how the media portrays genetic difference.