Heterochromia

ديسمبر 9, 2022

2 دقائق

We will discuss Heterochromia syndrome

Introduction

The process of sight, or vision, is characterized by being highly complex. So the majority of the brain is dedicated to this sense compared to the other senses combined. The visual system functions in a manner similar to that of the auditory system.

Firstly, Light enters the pupil, focuses on the retina at the back of the eye. Then that is converted by the retina into electrical impulses. finally, it’s travel via the optic nerve to the brain, enabling it to process light signals.

As a result of the quantity of melanin pigment in the iris determines its color. So it is the colored and most noticeable area of the eye. However, the iris’ color can vary for a variety of reasons, including a genetic abnormality or an eye injury.

:heterochromia syndrome

Heterochromia is a syndrome that leads to the difference in colors in the iris of the eye. In short the person can be identified by conducting a test for the concentration of melanin production in the eye. So this can occur completely or partially as If the entire iris of the eye changes. Or if only part of it changes, one iris remains to bear two colors, according to each case.

However, The phrase is frequently used to describe iris shade contrasts. Also be used to describe differences in skin or hair tones. The production, distribution, and convergence of melanin control heterochromia (a shade). It affects both people and specific kinds of domesticated animals.

: What causes heterochromia

The iris’ coloring ranges from light brown to black, depending on the amount of melanin present in the pigment epithelium (at the rear of the iris). However the amount of melanin present in the stroma (at the front of the eye), and the stoma’s cellular density. Complex genetics have a role in eye color.

: Genetic causes

Multiple genes contribute to the genetic characteristic of eye color. Another key points, these genes use connections to look for modest changes in their own genes and in genes nearby. These modifications are referred to as polymorphisms or single-nucleotide polymorphisms.

Certainly, there is proof that up to 16 separate genes might be in charge of determining a person’s eye color. But OCA2 and HERC2 on chromosome 15, are the two primary genes linked to changes in eye color.

– OCA2 is related to cells that produce melanin. The primary importance of eye color

– HERC2 affects OCA2 function, and one particular mutation is strongly associated with having blue eyes.

– SLC24A4 is connected with the difference between blue and green eyes.

– TYR is connected with the differences between blue and green eye color.

But in other instances, certain illnesses, such as Bourneville sickness, may be the source of hereditary heterochromia.

– Horner’s syndrome.

– Waardenburg syndrome.

– Hirschsprung disease.

– Recklinghausen disease (von Recklinghausen disease).

– Bloch-Sulzberger syndrome.