Deutan color blindness (also known as deuteranomaly) is the most common type of red-green color blindness in which the green cones in the eye detect too much red light and not enough green light. In other words, the sensitivity of the green cone is shifted toward longer wavelengths, becoming more overlapping with its neighboring red cone. It is estimated that 75% of people with color blindness are “Deutans”. As a result of the overlap, red, yellow, green, and brown can appear similar, especially in low light. It may also be difficult to tell the difference between blues and purples, or pinks and grays.