An illustration of a Manhattan plot depicting several strongly associated risk loci
A Manhattan plot is a type of scatter plot, usually used to display data with a large number of data-points - many of non-zero amplitude, and with a distribution of higher-magnitude values, for instance in genome-wide association studies (GWAS). In GWAS Manhattan plots, genomic coordinates are displayed along the X-axis, with the negative logarithm of the association P-value for each single nucleotide polymorphism (SNP) displayed on the Y-axis, meaning that each dot on the Manhattan plot signifies a SNP. Because the strongest associations have the smallest P-values (e.g., 10−15), their negative logarithms will be the greatest (e.g., 15).
It gains its name from the similarity of such a plot to the Manhattanskyline: a profile of skyscrapers towering above the lower level "buildings" which vary around a lower height.