Incidence of colourblindness in different Indian populations: further example of selection relaxation hypothesis

Incidence of colourblindness among 1154 males belonging to seven endogamous groups viz. Brahmins, Rajputs and Shilpkars of Pithoragarh (Uttar Pradesh), Brahmins and Rajputs of Simla (Himachal Pradesh) and Kolis and Rajputs of panchmahal [Gujarat] has been reported. The frequency of colourblindness varies from 1.74% in Shilpkars to 5.0% in Kolis. Further, Indian male population data have been divided into three categories on the basis of their mode of life and habitat to test Post, Pickford and Neel and Post's hypothesis of differential selection for colourblindness.