What does the OCA2 gene do?

The OCA2 gene (formerly called the P gene) provides instructions for making a protein called the P protein. This protein is located in melanocytes, which are specialized cells that produce a pigment called melanin. Melanin is the substance that gives skin, hair, and eyes their color.

Who does OCA2 affect?

In contrast, OCA2 is the most common type of albinism in African Black OCA patients. The overall prevalence of OCA2 is estimated to be 1:36,000 in the USA, but is about 1:10,000 among African Americans [4]. It affects 1 in 3,900 of the population in some parts of the southern part of Africa [5].

What does the OCA2 gene have to do with blue eye color?

Several common variations (polymorphisms) in the OCA2 gene reduce the amount of functional P protein that is produced. Less P protein means that less melanin is present in the iris, leading to blue eyes instead of brown in people with a polymorphism in this gene.

Is OCA2 a transcription factor?

transcription factors binding the promoter of OCA2 gene in low- or high-throughput transcription factor functional studies from the CHEA Transcription Factor Targets dataset. phenotypes associated with OCA2 gene from the curated ClinVar Gene-Phenotype Associations dataset.

What color eyes do people with OCA2 have?

The OCA2 gene also contains numerous regions for eye color expression. Over 300 SNPs for eye color have been identified on the gene, but classification of their results proved too arduous. The gene contains a main coding region for brown eyes (BEY2 15q11-15) and hazel eyes (BEY1).

Human Eye Color Lecture | PART-3 | OCA2 gene | P-protein | melanosomes | Basic Science Series

Does everyone have the OCA2 gene?

Oculocutaneous albinism caused by mutations in the OCA2 gene is called oculocutaneous albinism type 2. The prevalence of OCA type 2 is estimated at 1/38,000-1/40,000 in most populations throughout the world, with a higher prevalence in the African population of 1/3,900-1/1,500.

What kind of mutation is OCA2?

Oculocutaneous albinism

Other OCA2 gene variants, including changes in single DNA building blocks (base pairs) and small deletions, are more common in other populations. Variants in the OCA2 gene disrupt the normal production of melanin, which reduces coloring of the hair, skin, and eyes and affects vision.

What does MC1R gene do?

Normal Function. The MC1R gene provides instructions for making a protein called the melanocortin 1 receptor. This receptor plays an important role in normal pigmentation. The receptor is primarily located on the surface of melanocytes, which are specialized cells that produce a pigment called melanin.

How is OCA2 caused?

People with this condition usually have vision problems such as reduced sharpness; nystagmus and strabismus; and increased sensitivity to light (photophobia). This condition is caused by genetic changes in the OCA2 gene and is inherited in an autosomal recessive fashion.

What is HERC2 and OCA2?

Abstract. The OCA2-HERC2 locus is responsible for the greatest proportion of eye color variation in humans. Numerous studies extensively described both functional SNPs and associated patterns of variation over this region.

What protein does OCA2 produce?

The OCA2 gene (formerly called the P gene) provides instructions for making a protein called the P protein. This protein is located in melanocytes, which are specialized cells that produce a pigment called melanin. Melanin is the substance that gives skin, hair, and eyes their color.

Does having blue eyes mean your inbred?

Summary: New research shows that people with blue eyes have a single, common ancestor. Scientists have tracked down a genetic mutation which took place 6,000-10,000 years ago and is the cause of the eye color of all blue-eyed humans alive on the planet today.

What does it mean to have hazel eyes?

Opinions vary on what, exactly, constitutes hazel eyes. Some consider them to be any shade with light brown or gold tones; others think they are variation of brown eyes, only with more green or gold in the iris. Whatever the precise shade, scientists agree that hazel eyes are caused by light-scattering and melanin.

How rare is OCA2?

The prevalence of Oculocutaneous albinism type 2 (OCA2) is estimated at 1/38,000-1/40,000 in most populations throughout the world except in the African population that has a higher prevalence of 1/3,900-1/1,500.

What gene is responsible for albinism?

The enzyme produced by the TYR gene, called tyrosinase, is required for the synthesis of melanin pigment. A mutation in the TYR gene causes the most common form of albinism. People with albinism have either a partial or complete lack of pigment, or coloring, in their eyes, skin or hair.

Can an albino have a normal child?

This means a child has to get 2 copies of the gene that causes albinism (1 from each parent) to have the condition. If both parents carry the gene, there's a 1 in 4 chance that their child will have albinism and a 1 in 2 chance that their child will be a carrier.

Is OCA2 dominant or recessive?

OCA is an autosomal recessive disorder associated with mutations in genes which control the biosynthesis of the melanin pigment [1].

What causes green eyes?

Green eyes are a genetic mutation that produces low levels of melanin, but more than blue eyes. As in blue eyes, there is no green pigment. Instead, because of the lack of melanin in the iris, more light scatters out, which make the eyes appear green.

What gene controls redheads?

It had been thought that red hair is controlled by a single gene, called MC1R. The new research sheds light on other genes that are involved. Previous studies had shown that redheads inherit two versions of the MC1R gene that leads to red hair – one from their mum and one from their dad.

What mutation is the MC1R gene?

MC1R mutation is associated with Melanoma. Melanocortin-1 receptor variants are associated with high melanoma risk. It was suggested to be involved in Parkinson disease (PD) and melanoma, but its genetic variants do not play roles in susceptibility for Parkinson disease or rapid eye movement sleep behavior disorder.

Do all redheads have MC1R gene?

Although almost everyone with red hair has two copies of the red-haired version of MC1R, not everyone carrying two red-haired versions is a redhead.

What protein does albinism alter?

OCA1, or tyrosinase-related albinism, results from a genetic defect in an enzyme called tyrosinase. This enzyme helps the body to change the amino acid, tyrosine, into pigment. (An amino acid is a “building block” of protein.) There are two subtypes of OCA1.

Who was the first blue-eyed person?

A Stone Age man who lived about 7,000 years ago and whose buried bones were discovered in 2006 has turned out to be the earliest known person with blue eyes, a physical trait that evolved relatively recently in human history, a study has found.

Who is the common ancestor for blue eyes?

All blue-eyed people have one ancestor in common, born around 6,000 to 10,000 years ago. Blue eyes are caused by a gene mutation. For years, researchers had searched for it on the OCA2 gene. The OCA2 gene determines how much brown pigment is in our eyes.