Are Identical Twins Really Identical?

Identical twins, or monozygotic twins, are fertilized eggs produced by the combination of a sperm and an egg. This fertilized egg is divided into two, forming two embryos. Because they come from the same fertilized egg and receive exactly the same chromosomes and genetic material, they are the same sex and come out of a mold, sometimes even their parents can't tell.

Identical twins

Identical twins

How to identify whether they are identical twins or fraternal twins?

There are many methods of identification.

First, if the twins have different genders, then they must be fraternal twins (except for a pair of semi-identical twins born in 2001, one of them male and the other hermaphrodite). If the genders are the same, further differentiation is needed. At birth, your doctor may tell you whether two children are one or two placenta. One placenta indicates an identical twin, and two placenta are an fraternal twin. But this concept is wrong. Although the condition of the placenta and membranes has a certain relationship with the ovulation of the twins, it is not absolute, so you cannot judge based on this alone.

Generally people will judge by their appearance. Some twins are carved out of a mold. Most of them are identical twins, and most of them are not identical twins. This method does have some scientific basis. We call this method the similar method. However, appearance alone is not enough. It must also include some other characteristics, such as skin texture, hair color, hair form and density, eyes

A large-scale psychological experiment conducted by American universities in the 1930s.

Welfare agencies often give adopted children to people who adopt them. American universities and welfare agencies have collaborated to deliberately give identical twins to very different families for adoption. For example, differences in country, language, religion, personality of adoptive parents, education level, amount of wealth, occupation, etc. The goal is to see whether identical twins have the same personality during adulthood and after adulthood in completely different environments. In order to figure out whether it is the external environment or the innate gene that determines a person's personality.

The test results proved that identical twins grew up in different environments and still had very similar environments and experiences. It turns out that 50% of the factors that determine a person's personality are innate genes.

On August 6, 2012, according to foreign media reports, a lucky couple in the United Kingdom, when conceived naturally, was given the same triplet as a boy.

Triplets (2 photos)

It is said that identical triplets have a probability of one in 200 million.

The woman, Claire, reportedly lives in Bucksshire, near London, at the age of 33. In April 2012, Claire gave birth to a triplet in a hospital by laparotomy. The three babies stayed in the mother's abdomen for only 34 weeks. At birth, each baby weighed about 4 pounds (about 1.8 kg) and had to eat through the esophagus three weeks after birth.

It is reported that the triplets are so similar that it is difficult for even his mother Claire to distinguish. At first, Claire had to distinguish babies by making marks on their nails. ^[2]