The twelve different categories of disease are each associated with a different chakra, or scale, derived from the Melakarta ragams in Indian classical music. The lower four notes (tetrachord) for each chakra provides the harmonic background for each disease category, while the upper tetrachord represents the four DNA bases (ACTG), which play part of the DNA promoter sequence for each disease. The amount of DNA letters played depends on the number of genes associated with the disease.