Populations that have been isolated for generations make good subjects for scientists studying the genetic basis of diseases. But cultural sensitivities can sometimes create tension, particularly if compounded by personal clashes among the researchers.

Thus, a study of diabetes in an isolated tribe of Native Americans in Arizona, USA, has come to a bitter end. In this Nature article, Rex Dalton reports on how the project has led to a US$75 million lawsuit, with the Havasupai tribe claiming that researchers analysed blood samples without the tribe's consent. Discord between researchers — which prompted an independent report into the project — appears to have fuelled the tribe's own discontent.