From this search utility you can choose a SNP or SSR marker to examine in Panzea's Geographic Display. In this display, allele frequency spectra in different geographic localities are contrasted via pie graphs.

Use the Marker Name box to choose a particular SNP or SSR for which you would like to display allele frequencies in their geographic context. To see all available markers (sorted in descending order by number of geographically mapped data points), leave the search parameters in their default state and click on Submit. To see only SNPs or only SSRs, use the Marker Type box. The HTML table generated as a result of your search will contain a Geographic Display column -- click on the Geo. Map link within this column for a given marker to get to the Geographic Display for that marker.

The Panzea Geographic Display is based on Google Maps -- Map, Satellite and Hybrid views are available (choose your preferred view from the upper right corner of the map). The geographic area represented by each allele frequency pie graph is determined based on the map position and zoom level. A nine by nine grid is automatically placed upon the map and is regenerated each time the map is moved or with each change in zoom level. If one or more genotyped individuals originated from a particular tile in the grid, then an allele frequency pie chart will be displayed for that tile. The size of each pie graph reflects the sample size falling within the corresponding grid tile. Each (diploid) individual counts for two data points (two alleles). Click on a pie graph for more information on the sample size it represents, for the expected heterozygosity estimate based on that sample, and for a list of the alleles present along with their precise frequencies in the sample.

To reduce the visual comlexity of the display for an SSR you can choose a single allele to display by using the Allele Value drop down box and then clicking on Filter. The remaining alleles will then be combined and displayed in white in the pie graphs. Alternatively, you can lump rare alleles together using the Cluster rare alleles option and then clicking on Filter.

View or Download a Geographic Display tutorial