In a documentary, Deng Tiejun, a female DNA appraiser, told a true story, a couple gave birth to twins after marriage, but what made the man wonder was why the twin brothers did not look like each other at all. One of them had no resemblance to himself in terms of eyes, mouth, or nose.
The man gave the twins a paternity test, which revealed that the twins had two biological fathers. At that time, the staff said to the father: "You are lucky, at least one of them is your own birth". This made him instantly dumbfounded. The twins turned out to be half-siblings.
Twins, but the father is not the same person, what is this operation?
We need to know, and we all know that every fertile woman typically produces only 400 to 500 mature eggs in her lifetime, usually only 1 egg per month, and occasionally 2 or more eggs. Each male with fertility can excrete hundreds of millions of sperm at a time, and the combination of sperm and egg will form a fertilized egg, which will gradually develop into an embryo. The process of sperm-egg binding may occur like this:
1, that is, 1 egg and 1 sperm combined, giving birth to 1 child, the gender can be male or female.
2, under certain conditions, the newly formed fertilized egg will be divided into two, forming two independent individuals, that is, what we call identical twins. Generally identical twins are of the same sex.
3. Women only release one of the best-developed eggs per month, and most only give birth to one child. However, it is also rare for women to have two eggs a month. At the time of conception, there are two eggs and two sperm combined, and then develop into two independent individuals, which are more different after growing up, and can be of the same sex or the opposite sex.
4, semi-identical twins, in the fertilization process, there are two sperm combined with the same egg, such an embryo will produce three sets of chromosomes, 1 group from the mother, 2 groups from the father. This also means that in semi-identical twins, one set of genes comes from the egg and the other comes from two sperm. Heterosexual identical twins may then appear. This is so rare that to date only two semi-identical twins have been confirmed worldwide. And there are all kinds of problems in the body.
There is also a fifth, which is very rare, since the genetic material of fraternal twins comes from different sperm and eggs, theoretically, if a woman has sex with multiple men in a short period of time, and it happens that the woman produces multiple eggs during the same ovulation period, then the two eggs may combine with sperm of different men, resulting in the twins having two different biological fathers. This is also the reason why a pair of twins actually has two fathers.
Many people say that this interval is 6 minutes, but it is not, and scientists have found that the simultaneous re-pregnancy of the half-father can be attributed to "mating with multiple men in the 1 to 2-day fertility window of one ovulation and in the days before that.". Human sperm can survive more than 1 day in the female reproductive system, and a 1997 study suggested that sperm had a 5% chance of surviving more than 4.4 days in a woman and a 1% chance of surviving for more than 6.8 days – that's really long.
Even scientists have found that it is still possible to have half-siblings within 10 days of the interval between two intercourse. This is so because while some women release multiple eggs during the same ovulation period, the two eggs may not be released at the same time, sometimes a few days apart.
After learning the results of the report, the man held the paternity test report and angrily looked for his wife to theorize. The wife insisted on her faithfulness to her husband and even suspected that she had manipulated the samples sent for identification. But after the doctor's explanation, although the wife was also incredible, she had to admit that she had a "one-night passion" with other men.
This is not only the case at home, but abroad, where a Spanish woman gave birth to twins and her husband asked for DNA testing to determine if he was the real father. Tests showed that one of the completely different pairs of twin girls was 99.9999998% likely to be his child, but the other was clearly not. The test results also showed that they all had the same mother. The woman later admitted that she had had an extramarital affair during that time.
Because they are twins, as for how to arrange the two children, this estimate is a long process of ridicule.