Chromosomal polymorphism in Drosophila nasuta. III. Inverted gene arrangements in South Indian populations.

Inversion polymorphism, including a total of 33 inverted gene orders, was studied in South Indian populations of D. nasuta nasuta. Of these, the X chromosome has one, chromosome 2 has 10, and chromosome 3 has 22 inversions. D. nasuta nasuta has simple, tandem, included, overlapping, and complex types of paracentrics in its polymorphic system. The phylogenetic considerations of these gene orders are discussed.