Genetic diseases: Color blindness

Definition

In today's post on genetic diseases we want to raise awareness about color blindness. color-blindness It is genetic and affects the ability to distinguish colors normally. It is also known as color blindness, and its main consequence is the person's inability to distinguish between certain colors, especially green and red, and sometimes blue.

Causes

Most people with color blindness are born with it. That is, it is a congenital disease. The sensory cells (photoreceptors) of the eye retina that react in response to light and are of two types: cones and rods . Rods are more sensitive to light but are incapable of perceiving colors, while cones are responsible for color vision. Therefore, when one or more of these color photoreceptors are not functioning or are absent, a different color is perceived.

Genetics of the disease

Color blindness is a genetic disease that is transmitted by a X-linked recessive allele , so it affects men more than women. That is, if a male inherits an X chromosome with the altered allele, he will be colorblind. However, in the case of women who have two X chromosomes, they will only be colorblind if both of their X chromosomes have the altered allele.

Symptoms

People with color blindness have an inability to see some shades of red and green. Often, a person with a deficiency in red and green or blue and yellow can perceive both colors to some extent.

Diagnosis

Diagnosing color blindness at an early age is important because it can prevent learning problems during the school years. Tests such as the following are often used to diagnose it:

• Test of Ishihara . It consists of sheets of circles in soft colors that draw numerous little paths, which the child must identify.
• Test of Farnsworth-Munsell . It is made with colored chips with different shades numbered on the front, which the child must arrange according to the color range.
• Genetic testing would also be important for the study of some variants of color blindness such as achromatopsia, which is why in www.genotica.com we have tests who study this type of diseases, as is the case of NGS-SEQ+CNVs – ACHROMATOPSIA from Lorgen.

Treatment

Unfortunately, there are no treatments for most types of color vision difficulties. However, wearing a colored filter on glasses or a colored contact lens can improve contrast perception between confusing colors.