Eye Color; Myths of Genetics

There are many myths regarding genetics and inheritable traits. Even when most of them have been clarified, people are still confused about some patterns of heredity. One of the most popular myths of genetics is eye color, specially those in the blue category since it is less common.
People used to believe that eye color were single genes, and that blue is a recessive allele of other non-blue eye colors like greens and browns. A research on myths of human genetics by John McDonald notes that eye color is not a simple hereditary trait, in fact there is at least 12 genes involved and phenotypes vary not only with the genes themselves but also with the interactions with each other.

Heterochromia: Different pigmentation/concentration of melanin.

Many articles explain that the coloration of the eyes is mainly based on the presence and absence of melanin, and that essentially there is only one eye color, brown; other colors are a product of reflection and absorption of light. Melanin is a brown pigment that absorbs light; in blue eyes, there is less melanin thus more light is reflected. For eye color, there are genes that determine the melanin's quality, quantity, dispersion, concentration, etc. Other factors like the amount of collagen in the iris and blood vessels can also affect the color expressed. Eye color is still believed to be genetic but is more complicated than simple dominant-recessive alleles.

Blood Type Diet Debunked

In the late 90's, Dr. D'Adamo came out with the book "Eat Right 4 Your Type", in which he writes about what each person should be eating, based on their blood type. Although this diet was created quite some time ago, people have been following it religiously, and blindly. It sounds super sciency, right; eating a diet strictly based off of your blood type? Well, it turns out that there is almost no science behind it at all, at least not any accurate science. The book gives a list of foods for each of the 4 blood types, consisting of what each one should eat, shouldn't ever eat, and what's basically neutral. Unfortunately, all of the "science" Dr. D'Adamo used to support these lists was complete nonsense. However, that didn't stop all of the celebrities, naive teenagers, and desperately overweight people from buying into it and swearing to the diet.

The problem was that it was a really cool idea, thinking that you could follow a perfect diet by doing exactly what the book said because, it matches your genetic makeup, right? Well, it's all null and void as soon as you research any of his "facts" and realize that it's almost all wrong. All he did was pick a very low carb, low fat, vegetarian diet for the most common blood type (Type O) and of course, by following it, a heck of a lot of people lost weight. But that had nothing to do with their blood type, it just had to do with the fact that that's the healthiest kind of diet you can eat! So of course most people saw results because they were simply eating healthier! People like Dr. D'Adamo take advantage of those who are desperate and too lazy to educate themselves because they are just waiting for a miracle to happen, and it's a little bit of both parties faults. So this is a good lesson to remember to not believe everything you read, even if it did come from a doctor; and to always do your own research!

http://www.refinery29.com/2016/07/116159/blood-type-diet-myths
https://nutrino.co/blood-type-diet-debunked/