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A haplotype present in Africa and absent elsewhere showed evidence for recent selection by the Long-Range Haplotype (LRH) test, using data from the International Haplotype Map Consortium (Altshuler et al. 2005). The signal of selection spans 60kb across the CD36 gene. The peak signal spans a 20kb region centered around exon 10 of the gene. Closer inspection showed the haplotype with strongest evidence for selection contains a nonsense mutation (amino acid changed to a stop codon), T188G, that has been associated with differential susceptibility to Plasmodium falciparum cerebral malaria (Aitman et al. 2000; Pain et al. 2001). This prototype browser by Ben Fry shows how we discovered the key mutation and demonstrates how one can visualize potential key functional changes. The animated browser is designed to show varying zoom levels of a genetic region of interest. You can move your mouse over each level to scan through the data. Or click on particular features to immediately move to points on the browser. Top level: the genes contained in the broader 500kb region of interest. Middle level: the exons within each gene in a 100kb window. At this level there are indicators for potentially important changes, particularly amino acid changing mutations (yellow markers) and mutations in regions conserved across chimpanzee, mouse, and dog (blue markers). All human polymorphisms are indicated below for reference (black markers). Lower level: the DNA sequence in human, chimpanzee, mouse, and dog for a 160bp region. For gene exons, the amino acid sequence is given at the top. If there is an amino acid changing mutation, the alternate amino acid is listed below. The row labelled ‘human’ gives the DNA sequence in humans. Human polymorphisms are presented with the two nucleotides placed one on top of each other. Nucleotides in red are human polymorphisms or fixed differences with chimpanzees in regions that are conserved between chimpanzee, mouse, and dog. The DNA sequence for chimpanzee, mouse, and dog are shown at the bottom. Nucleotides in grey are shared with humans. Nucleotides in black are different from the human. Aitman TJ, Cooper LD, Norsworthy PJ, Wahid FN, Gray JK, Curtis BR, McKeigue PM, Kwiatkowski D, Greenwood BM, Snow RW, Hill AV, Scott J (2000) Malaria susceptibility and CD36 mutation. Nature 405:1015-1016 Altshuler D, Brooks LD, Chakravarti A, Collins FS, Daly MJ, Donnelly P (2005) A haplotype map of the human genome. Nature 437:1299-1320 Pain A, Urban BC, Kai O, Casals-Pascual C, Shafi J, Marsh K, Roberts DJ (2001) A non-sense mutation in Cd36 gene is associated with protection from severe malaria. Lancet 357:1502-1503