This results in a hair fiber that has an elliptical shape, which allows it to curl. How exactly the different types of twists, kinks, and waves are created from this elliptical shape has eluded scientists so far. But what controls these processes? Scientists know that our genes control hair shape.
So far, the main driver to have been identified is a gene that produces a protein called trichohyalin TCHH , which strengthens the growing hair.
The TCHH gene contains distinct variants called small nuclear polymorphisms, which are associated with different hair shapes in people across the globe. For example, in individuals of East Asian decent, variations in the gene for the receptor EDAR are associated with straight, coarse hair. There are a handful of additional genes that have recently been identified and might play a role in regulating hair shape.
Interestingly, some of these are speculated to be under epigenetic control, which means that how they are expressed can be inherited from your parents or even be affected by your environment. So, the next time you look at your hair and wish that it were a different shape, rest assured that scientists are working on figuring out the precise mechanisms that determine your locks.
Hair thinning and hair loss are common, and manufacturers offer many products to help combat these conditions.
Learn about some of the best products…. Viviscal dietary supplements are oral, drug-free hair growth tablets. The manufacturer claims they promote existing hair growth and nourish thinning….
Regenix offers personalized treatments for hair loss using natural ingredients. Click here to learn more. HairMax sells laser devices that may treat hair loss and thinning.
Read on to learn more about HairMax, the effectiveness of the products, and where…. Shimomura Y, Christiano AM. Biology and genetics of hair. Annu Rev Genomics Hum Genet. Other chapters in Help Me Understand Genetics. Genetics Home Reference has merged with MedlinePlus. Learn more. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.
Is hair texture determined by genetics? From Genetics Home Reference. Topics in the Genetics and Human Traits chapter Are fingerprints determined by genetics? Is eye color determined by genetics? Is intelligence determined by genetics? Is handedness determined by genetics? Your follicle shape is partly determined by what genes you have.
Your DNA might cause you to have perfectly round follicles. In this case you would have straight hair. Or your DNA might cause you to have oval-shaped follicles, leading to curly hair. In this case, your follicles would be a little bit in the middle! You would have wavy hair. The shape of your hair follicle determines if you have straight, wavy, or curly hair. But we do know a little bit about how these genes can get turned on or off. Genes can turn on and off for lots of different reasons.
These factors are not even completely understood by scientists! But we do know that hormones can turn genes on and off. Several hormones have been implicated causing changes in hair texture. Hormones are chemical signals that the body uses to send messages between body parts. Your hormone levels can change a lot during your life. Changes in age, nutrition, temperature, sun exposure and various other factors can cause our bodies to change the amounts or types of hormones we make.
Some women report that their hair became thicker and glossier during pregnancy.
0コメント