Curly hair is dominant, so someone is more likely to have curly or wavy hair if at least one of their parents does. Recent research points to trichohyalin, a protein in hair follicles, as having primary influence over hair curl. However, there are many genes contributing to hair curliness, most of them unknown.
In that case, the dominance (recessiveness) of the gene determines what the hair type of the child is. It could be that neither of your parents have curly hair, but an ancestor did.
Despite the genetic differences, research shows that curly hair is predominantly a result of genetics. Individuals who have a parent with curly hair are more likely to have curly hair. However, cultural norms have also played a role in shaping African American women's relationship with their curls.
The gene for curly hair in Caucasians
It has been long established that curly hair is a dominant trait in Caucasians and straight hair is recessive.
Less than 20% of people have naturally curly hair.
The story of human migration and evolution is written in hair DNA. In sub-Saharan Africa, genes favour tight, curly hair. But in east Asia, mutations have led to straighter, thicker hair. In Europe, other mutations brought wavy and straw-coloured hair.
We believe one of the reasons is that super-straight hair — also known as type 1a hair — is so rare. In fact, it's the rarest hair type. Only 2% of the world's population has 1a hair. It's mostly found in people of Asian descent.
One popular myth is that hair loss in men is passed down from the mother's side of the family while hair loss in women is passed down from the father's side; however, the truth is that the genes for hair loss and hair loss itself are actually passed down from both sides of the family.
Yes, only 11% of the population have curly hair.
Genetically, you actually carry more of your mother's genes than your father's. That's because of little organelles that live within your cells, the mitochondria, which you only receive from your mother.
And while the results did vary, in the end we found that 58% of the fellas agreed that curlier is sexier.
It's a gene thing thats all. The answer is genetics. The DNA you and your siblings receive is what determines the characteristics of your hair.
Over 60% of the world's population has curly hair, yet most research to date has clumped hair into three catchall types - African, Asian, and Caucasian.
The probability of the parents having a child with curly hair is 3/4, as shown in the Punnett square below: A Punnett square for the cross of two heterozygous parents is shown.
So for hair type, CC gives curly, Cs gives wavy and ss gives straight hair. Back to your specific situation. As you can probably tell, the couple you describe could only have wavy haired kids. That is because the curly headed parents, CC, can only contribute a C gene and the straight haired parent, only an s gene.
Unlike nuclear DNA, which comes from both parents, mitochondrial DNA comes only from the mother.
Your children inherit their eye colors from you and your partner. It's a combination of mom and dad's eye colors – generally, the color is determined by this mix and whether the genes are dominant or recessive. Every child carries two copies of every gene – one comes from mom, and the other comes from dad.
A general observation across experiments was that straight hair was perceived as younger, healthier, and more attractive than wavy hair and darker shades (medium copper and brown) were perceived more positively than blonde hair.
Coily Curls
The last, but most rare type of curl is the coily curl. This curl type is similar to that of an afro and when observed carefully, looks like the angular letter 'Z'. These curls require the most amount of moisture, as the hair type is much thicker than the other curl types.
Curly hair is often associated with a fun-loving, warm hearted and outgoing personality. If you have curly hair you are perceived as being courageous, outspoken, and spontaneous. You are probably someone who likes to challenge perceptions and norms. You celebrate your uniqueness and value your roots.
Hair that is tightly coiled offers the best protection against the sun's potentially damaging rays, which could explain why this trait evolved in early humans in Africa and straighter hair emerged as some humans moved into cooler areas.
The terms 'European hair' and 'Caucasian hair' are often used interchangeably and are taken to denote 'wavy' to 'straight' hair; 'East Asian' hair is taken to mean 'pin-straight' hair; and 'African' or 'ethnic' hair is taken to signify 'curly' or 'very curly' hair.