Twins boy and girl

What does it mean royal twins - the mystery of nature,Or a gift of fate for selected parents? Can it be a serious test? Of course, two outwardly similar, but at the same time different-sexed karapuza - daughter and son - this is real happiness. But at the same time - a great responsibility, and if you add the risk of various gene deviations, it may be good that such pairs meet one in a thousand. </ P>

According to statistics, twin children are a boy andA girl is a phenomenon so rare that when she learns about multiple pregnancies, many mothers and dads, and even doctors, do not assume that royal twins can be born. After all, unisex babies, most often are the result of the fertilization of two eggs, that is, twins, but not twins. Nevertheless, stories are known cases when simultaneously a light appeared brother and sister, similar to each other as two drops of water.

So are the twins, or all the same twins, a born boy and girl with an almost identical gene set? Let's try to figure it out.

Could a similar boy and girl be twins?

It is impossible to deny that fact, and a little bit of light has been shed by the science of the mysterious birth of the unisex twins. Yes, it can be, although extremely rare.

We all know from the lessons of anatomy that the twinsAppear from a single zygote and have the same chromosomal set. But there are a number of factors and inexplicable processes in which twins appear: the boy and the girl. Let's look at when this is possible:

  1. If one of the boys' twins "lost" the Y chromosome. This phenomenon rather refers to the number of anomalies and is referred to as Turner syndrome.
  2. When one child has one extra X-chromosome (Clinfelter's syndrome).
  3. In case the egg had time to share before fertilization. In such cases, fertilization takes place with different spermatozoa, and it is likely that the twins will be of opposite sex.
  4. If the egg (the egg itself and its polar body) is impregnated by two male cells.

    Children twins boy and girl

    In such cases, babies are born healthy, without any gene anomalies.

How to conceive the twins of a boy and a girl?

The process of formation of monozygotic heterozygousTwins are very complex and not fully understood. Therefore, no matter how much parents want to give birth to the boy's twins and the girl, it is almost impossible to predict or influence this process in advance. Although science does not stand still, and along with the massive introduction of IVF, future moms and dads have a prospect in the future to pre-order the gender of the kids and their identity.