What Causes Color Blindness?

Congenital color vision disorder is usually called color blindness, it can't distinguish various colors or a certain color in the natural spectrum; and those who have poor ability to distinguish colors are called color weakness, and those with weak colors can see the colors seen by normal people. However, the ability to recognize color is slow or poor. When the light is dark, some are almost the same as color blindness, or it is expressed as color vision fatigue. It is generally not easy to strictly distinguish the boundary between color blindness and color blindness. Congenital factors are more common in color blindness and color weakness. There are far more men than women.

The genetic laws of color blindness

When it comes to color blindness, Dalton, a British chemist, has to be mentioned. He is a red-green blind person and the first person in the world to raise the issue of color blindness. Color blindness refers to the inability to distinguish various colors in the natural spectrum. Color blindness is divided into full color blindness and partial color blindness, and some color blindness is red green blind and blue yellow blind.

How is color blindness formed? More

Color blindness can't distinguish any color or a certain color in the natural spectrum. Why do people get color blindness? This is mainly due to mutations in human color recognition genes. Human red and green recognition genes are on the X chromosome. When this gene is mutated, it will cause color recognition disorders.

How is color blindness inherited? More

Color blindness is a genetic disorder of the X chromosome. If men are color blind people, they need to marry a normal woman. The boys born to them are normal and the girls are carriers of the color blindness gene. If women are colorblind, regardless of whether their spouse is colorblind, boys in their offspring must be colorblind, and girls become colorblind or carriers of colorblind genes.

Related entries:

John Dalton Red Green Blind

Content collation: nuclear energy

Basic Information

English name

color blindness

Visiting department

Ophthalmology

Common causes

Due to chromosomal inheritance

Common symptoms

Color weakness and red-green blindness are more common

Causes of color blindness

It is generally believed that red-green blindness is determined by two pairs of genes on the X chromosome, namely the red-blind gene and the green-blind gene. Because the two pairs of genes are closely linked on the X chromosome, they are often represented by a gene symbol. The inheritance of red-green blindness is X-linked recessive inheritance. Men have only one X chromosome, so they only need one colorblind gene to perform well. Women have two X chromosomes, so they need a pair of disease-causing alleles to behave abnormally. If a normal woman is mated with a color blind man, the father's color blindness gene can be transmitted to their daughter along with the X chromosome, but not to their son. The daughter passed the color blindness gene from her father to her son, a phenomenon called cross-heredity.

Clinical manifestations of color blindness

Color blindness is divided into full color blindness and partial color blindness (red, green, blue and yellow, etc.). Color weakness includes full color weakness and partial color weakness (red weak, green weak, blue yellow weak, etc.).

Full color blindness

It belongs to complete cone cell dysfunction, which is just the opposite of night blindness (rod cell dysfunction). Patients are particularly faint and light-fearing, showing day blindness. There is only difference between light and dark, and there is no color difference, and what you see is dark red and blue light. In addition, there are symptoms such as poor vision, amblyopia, central dark spots, and oscillating nystagmus. It is the most severe form of color vision disorder and is rare.

2. Red blind

Also known as the first color blindness. Patients are mainly unable to distinguish red, red and dark green, blue and magenta, and purple. Green is often regarded as yellow, purple as blue, and green and blue are mixed into white.

3. Green blindness

Also known as second color blindness, patients cannot distinguish between light green and dark red, purple and cyan, magenta and gray, and regard green as gray or dark black. Red blindness and green blindness are collectively referred to as red-green blindness in clinical practice, which are more common. Color blindness usually refers to red-green blindness.

4.Blue-yellow blind

Also known as the third color blindness. The patients are confused with blue and yellow, and can distinguish between red and green, which is rare.

5. Weak color

Also known as red green blue yellow weak. The color vision disorder is lower than full color blindness, there is no abnormality in vision, and there are no other complications of full color blindness. It can be distinguished when the object is dark and bright; if the color is light but not saturated, it is difficult to distinguish, which is rare.

6. Partial color weakness

There are weak red (weak first color), weak green (second weak color), and weak blue and yellow (third weak color). Among them, red and green are weaker. Patients have poor sensitivity to red and green. The color ability is close to red and green blindness; but when the material color is deep, bright and the illumination is good, its color discrimination ability is close to normal.

Color blindness check

Color blindness and color weakness are mostly subjective inspections. They are generally performed under brighter natural light. The common inspection methods are as follows

False homochromatic diagram

It is usually called a color blind book. It uses dots of the same shade and different colors to form numbers or graphics. People with color vision impairment are difficult to recognize, wrong or unable to read. You can confirm what color vision abnormality belongs to according to the color blind table.

2. Color wire harness test

It is to mix the different color, different shades of yarn bundles, so that the subject will pick out the same color as the standard harness. This method is time consuming, and can only be qualitative but not quantitative, and is not suitable for large-scale screening tests.

3.Color mixing tester

It can quantitatively record the amount of red and green light matching required to determine the abnormality of red and green perception. This method can be both qualitative and quantitative.

Color blindness treatment

Acupoint and acupressure method

Shiatsu is located 2 cm below the center of the eyeball to improve eye function. During shiatsu, press for 6 seconds while exhaling. Shiatsu with open eyes and Shiatsu with closed eyes can be used.

When you open your fingertips, you can clearly determine the color. When you close your fingertips, you can treat abnormal vision and pseudomyopia. If you have a strong color abnormality, you should focus on the pressure. Repeated shiatsu will gradually eliminate the abnormal color vision.

2. Color Blind Corrector

The principle of the color blindness correction lens is to apply special coating on the lens according to the color compensation antagonism, which has the effect of cut-off wavelength. It can transmit to the long wavelength and reflect to the short wavelength. Wearing color-blind glasses can make the original color-blind picture unrecognizable become correct. To achieve the effect of correcting color vision disorders. Color blindness correction lenses are divided into contact lens type and ordinary wide frame type.