Did you know the ancient Greeks considered having one eyebrow beautiful? Other cultures believe thicker eyebrows are attractive. Not everyone is born with the same eyebrows. Whether you pluck your eyebrows to make them thin or allow them to grow thicker, the thickness of your eyebrows lies in your genes. In this blog, we will learn more about why some people have thicker eyebrows and how genes influence them.
Why Do Some People Have Thick Eyebrows?
Having thick eyebrows has a lot to do with your genes, and that’s why this trait often runs in families.
While no single region or ethnicity is responsible for the origin of thicker eyebrows, the trait has had an interesting journey through time.
Ancient Egyptians used black paint to thicken their eyebrows to match those of their god, Horus.
Post WWII, women began to grow their eyebrows out, a trend pioneered by the most prominent celebrities of the time, including Marilyn Monroe.
Today, thicker eyebrows are commonplace.
Are Thick Eyebrows Genetic?
Thick eyebrows are more than just a good grooming routine.
While there is limited knowledge about why some people have thicker eyebrows, it is certainly genetic to an extent.
Are Thick Eyebrows Dominant Or Recessive?
Thick eyebrows are a dominant trait compared to thin eyebrows.
If one of your parents has thicker eyebrows, you’ll likely have them, too.
However, more research is required in this regard.
Do Eyebrows Come From Mom Or Dad?
Eyebrow thickness is a dominant, non-X-linked trait.
You can inherit the trait from either parent if they carry it.
Current evidence suggests that several genes can influence eyebrow characteristics.
The exact mode of inheritance could differ for each gene.
What Genes Cause Thick Eyebrows?
Researchers have identified three previously unreported genes linked to eyebrow thickness in people of European descent– SOX11, MRPS22, and SLC39A12.
Similarly, two genes– SOX2 and FOXD1 have links to eyebrow thickness in non-Europeans.
Two other eyebrow-related genes, EDAR and FOXL2, usually express themselves in non-Europeans but do not affect Europeans.
Studies have shown that a specific region on the EDAR gene can help predict the thickness of eyebrows.
Mutations (abnormal changes) in this EDAR gene can also lead to dysfunction of other hair characteristics.
What Genetic Condition Has Thick Eyebrows?
Thick eyebrows are also a common symptom of several genetic conditions.
A few of these conditions include:
- Cornelia de Lange Syndrome is characterized by stunted growth, intellectual disability, and bone abnormalities.
- Rubinstein-Taybi Syndrome 2 is characterized by abnormal brain development, short statures, and broad thumbs & big toes.
- Autism spectrum disorder due to AUTS2 deficiency, characterized by poor social skills and delayed intellectual development.
- Coffin-Siris syndrome is characterized by coarse facial features, excess hair growth, and delayed speech/motor development.
Other Genetic Aspects Of Eyebrows
If you think the appearance of your eyebrows has more to do with grooming, think again!
The way your eyebrows look has more to do with your genes.
Eyebrow Shape
Four genes have been identified that affect eyebrow hair texture, one gene that determines the shape, and five genes that influence eyebrow color.
While your genes determine the shape of your eyebrows, environmental factors can also influence how your eyebrows look.
For example, years of waxing and tweezing eyebrows can affect their shape.
Any damage or injuries to the skin near the eyebrows can also affect hair growth and shape.
Are Unibrows Genetic?
A unibrow or synophrys is a normal variation of the human eyebrow.
In many ancient cultures, having a unibrow was considered an attractive feature in men and women.
Today, however, the Western civilization finds a unibrow unattractive.
Like other attributes of eyebrows, having a unibrow is also influenced by genes.
The inheritance of a unibrow is polygenic. This means several genes may influence the appearance of a unibrow.
A unibrow has also been associated with developmental defects or syndromes, such as:
- Cornelia De Lange syndrome
- Duplication 3q syndrome
- Frontometaphyseal syndrome
- Waardenburgh’s syndrome
- Partial chromosome 15 trisomy
Other FAQs About Eyebrow Thickness And Genetics
Let’s learn more about eyebrow thickness and genetics in these FAQs:
What Increases Eyebrow Thickness?
If you have thin or narrow eyebrows, there are many remedies that you can use to increase the thickness of your eyebrows:
- Apply coconut oil
- Use tea tree oil or lavender oil
- Saw palmetto
- Smart grooming
- Topical application of bimatoprost (only on the advice of a dermatologist)
- Eyebrow massage
Are Thick Eyebrows A Masculine Trait?
Men usually have thicker eyebrows than women.
Therefore, thicker eyebrows have always been perceived as a masculine trait.
However, many women have thicker, bushy eyebrows.
Which Gender Has A Thicker Brow Ridge?
Men tend to have thicker brow ridges than women.
This can be attributed to several factors:
- More prominent supraorbital ridge (ridge above their eyes)
- Steeper forehead angle
- High testosterone levels in men during puberty can cause the development of thicker bones, including the brow ridge.
Summary: Are Thick Eyebrows Genetic?
- The appearance of your eyebrows, including their thickness, is determined by your genes.
- Eyebrow inheritance is polygenic, meaning many genes can influence eyebrow appearance, color, and thickness.
- A few genes associated with thicker eyebrows are SOX11, MRPS22, SLC39A12, SOX2, FOXD1, EDAR, and FOXL2.
- While anyone can have thick eyebrows owing to their genes, this feature is also found in several genetic conditions, such as Cornelia de Lange Syndrome and Rubinstein-Taybi Syndrome 2
- The inheritance of a unibrow is polygenic. This means several genes may influence the appearance of a unibrow.
- Men tend to have thicker brow ridges than women, influencing their thicker eyebrows.
Expert-recommended Reads:
Double Eyelashes (Distichiasis)- Why Does It Happen?
Is Curly Hair Genetic? How DNA Affects Your Hair Type
Is Dandruff Genetic? Understanding The Roots
References
- https://www.elsevier.com/about/press-releases/the-look-of-your-eyebrows-is-in-your-genes-a-new-study-uncovers-genes-that-define-the-appearance-of-eyebrows
- https://genomelink.io/traits/eyebrow-thickness
- https://www.sciencedaily.com/releases/2023/06/230605181239.htm
- https://www.23andme.com/topics/traits/unibrow/
- https://www.chegg.com/homework-help/questions-and-answers/imagine-eyebrow-thickness-sex-influenced-trait-humans-determined-autosomal-gene-two-allele-q122661765
- https://www.ancestry.com/c/traits-learning-hub/unibrow