For a family, the joy of welcoming a twins is happiness doubled.However, for a father of two twin children in Xiamen City, Fujian Province, his mood is a kind of joy and sadness.In the process of raising children, he realized that two twin boys did not have the same similarity in appearance.Strangely, only one of the two children was like him but the other did not have any similar characteristics.
This problem made his heart very sad, when looking at the baby unlike him, he appeared a sense of doubt he was not a biological father.But when looking at the other baby, very much like him, he felt very guilty, could he suspect his wife?
One day, in order to make household registration for 2 children, he took his children to test the father and son.What makes him confused when reading the result is: One child is his biological son but the other boy has no blood relationship.Before her husband's anger, the wife sincerely confessed, she had a relationship with another man.But in the end, both husband and wife could not explain the fact that the two twin children had two different biological father.
After completing the sex, 300 million sperm began the hard journey.In the process of "racing", sperm will be "swallowed" by white blood cells at any time.
After many obstacles, only a few dozen to a few hundred sperm reach the fallopian tube to find the egg.At this stage, usually only a single sperm is lucky to be successful.This is because women only have one egg per month, resulting in a majority of people born only one child in 1 birth.
However, there are also rare women who fall 2 eggs per month.At this time, if a woman has sex with 2 men with short distance before or after ovulation, the two eggs can be fertilized with the other two sperm.And so, a pair of twins in the same pregnancy formed.This is called twins other eggs and is why a twin pairs can have 2 fathers.
But, the strangeness of multiple pregnancy does not stop there.In England, a mother gave birth to a pair of twins with completely different skin color, 1 black and 1 white.But the special thing is their appearance.
As we all know, after sperm and eggs combine, they create DNA together.At the end of the synthesis process in Trung Tu will have an egg fertilized with a complete set of human genes.However, there will be exceptions.Under certain conditions, the newly fertilized egg will be divided into 2 independent individuals.These two individuals will develop into 2 different embryos to create twins with eggs.
Illustrations of twins and eggs (left) and twins other eggs (right).
In short, the genes of twins are identical.That is why many twins are identical from appearance to personality.Skin color is determined by genetic genes and in some cases, many twins have the same appearance but one black and the other has white skin.What is the reason?
Currently, science believes that there are only two possibilities for such skin color differences.The first is the SOMA mutation in the process of embryo development immediately after the embryo division.If the reason is a Soma mutation, it is likely that it is the reversal of the transposon mutation(The jump gene or the displacement factor is the gene that changes its position in the genome).
The so -called displacement is like this: DNA is transformed into RNA and then RNA transforms the opposite code into CDNA.Such a CDNA type is called a displacement factor.With a displacement factor, the gene that regulates black pigmentation in the embryo has stopped working again, leading to the formation of a pair of twins different from the skin.
Another possibility is the difference in the sympathy (the development process of the organism, including the morphological change, the cells are differentiated and formed the organs).This means that 2 embryos have different birthborn processes.
In addition to the identical twins, but there are many different cases of color miracles such as the different twins.
In 2007, an American nationality woman had twins with eggs but had different gender.To analyze the fetal gene, the doctors took the amniotic fluid sampling around the fetus.As a result, the two fetuses have the same gene as the mother's genes, but the father's genes are only 78%.This is the phenomenon of twins selling eggs.
Artwork how to form 3 types of twins (from the top down): twins, twins with eggs and twins selling eggs.
Until now, only 2 cases have been confirmed as twins selling eggs worldwide.However, these children do not have a normal life after birth.The first pair of bronze eggs was born in the US in 2007 as written above, they were hermaphrodite with abnormal genitals.
Another case occurred in Australia, when the twins were 33 weeks, the mother discovered one of the two fetuses with abnormalities.Shortly thereafter, they were born early by caesarean method.However, they have no unusual signs with the genitals.
After birth, one of the two children was discovered seriously coagulated and forced to amputate his right hand at 4 weeks of age.By the age of 3, this child had gonadal dysgenesis and had to undergo surgery to remove the ovaries.
Fortunately, they are now 5 years old.
Source: Zhuhu