一、色觉的生理学基础在介绍色觉的分子遗传学之前,有必要提及一下色觉的生理学。人们知道,正常的色觉有赖于视网膜中三类视锥细胞的存在,每一类细胞各含有一种分别对红、绿和蓝光最敏感的感光色素。第四种色素存在于视杆细胞之中,它构成黄昏时无色视觉的基础。这四种色素的最大光吸收值分别在约430nm(蓝色—敏感色素)、530nm(绿色—敏感色素)、560nm(红色—敏感色素)和495nm(视杆细胞色素)处。视色素为整合的膜蛋白质。每一种视色素都由一种蛋白质分子 First, the physiological basis of color vision Before introducing the molecular genetics of color vision, it is necessary to mention the physiology of color vision. It is known that normal color vision depends on the presence of three types of cones in the retina, each of which contains a photographic pigment that is most sensitive to red, green and blue light, respectively. The fourth pigment exists in rods and forms the basis of colorless vision at dusk. The maximum absorbance values ​​of these four pigments are at about 430 nm (blue-sensitive dye), 530 nm (green-sensitive dye), 560 nm (red-sensitive dye) and 495 nm (rod cytochrome), respectively. Retinoids are integral membrane proteins. Each visual pigment consists of a single protein molecule