HIV Custer Concept Graphic (IMAGE) University of California - San Diego Caption Example HIV genetic transmission cluster including multiple transgender women (shown as purple hexagons). Nodes are colored to denote risk factor: men who reported sex with other men are blue squares and heterosexual men are red squares. Genetically similar viruses are denoted by links between the nodes. Credit UC San Diego Health Usage Restrictions Use caption and credit License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.