Advantages and disadvantages of identical or fraternal twins
Since the IVF technology has aroused widespread concern and application in the medical community, it has brought good news to those couples who cannot conceive naturally. However, when couples decide to have twins through IVF technology, an important problem they face is to choose identical (MZ) twins or fraternal (DZ) twins. These two types of twins have their advantages and disadvantages, which are described in detail from four aspects below.
1. Genetic characteristics
Identical twins are formed by the fertilization and division of the same sperm and egg at the same time, so their genetic genes are identical and their appearance is very similar. This makes identical twins have more in common in the process of growth, such as intelligence level and personality characteristics. In contrast, fraternal twins are formed by the simultaneous fertilization of two different eggs. Their genetic similarity is only 50%, which is the same as that of other siblings. Therefore, different twins are more likely to have different appearance and personality characteristics.
However, the genetic similarity between identical twins may also lead to some problems, such as disease risk. If one identical twin suffers from a genetic disease, another twin is also more likely to suffer from the same disease. In contrast, the genetic relationship between fraternal twins is relatively far away, and the risk of disease is low.
2. Pregnancy probability
The incidence of identical twins is about three times that of fraternal twins, because identical twins are formed in the early division process after fertilization. Therefore, the pregnancy probability of selecting identical twins through IVF technology is higher. In addition, the incidence of identical twins is also affected by genetic factors. If parents or grandparents have the genetic history of identical twins, they are more likely to choose identical twins.
3. Identity and intimacy
Identical twins have a high sense of mutual recognition and intimacy from birth. They have the same appearance, voice and DNA, so they can better understand and support each other in many aspects. They usually have deep emotional ties and can become good partners who rely on and support each other.
The closeness between fraternal twins may be relatively low. Although they also come from the same family, their differences in heredity and appearance will lead to more differences in personal characteristics and interests. However, they can cultivate their independence and personality in their mutual differences.
4. Brothers and sisters
Identical twins usually have a different relationship with ordinary siblings, and they are more closely connected. Identical twins often form a unique community and tacit understanding, and they can spend happiness and difficulties together. Like other brothers and sisters, fraternal twins grow up together, influence each other and establish unique family relationships.
summary
The selection of identical or fraternal twins as a way of IVF requires consideration of multiple factors such as genetic characteristics, pregnancy probability, identity and intimacy, and sibling relationships. Identical twins have higher genetic similarity and pregnancy probability, as well as higher sense of identity and intimacy; The genetic relationship between fraternal twins is far away, and there are more individual differences, but they can also establish a variety of sibling relationships. Therefore, couples should choose the twin type of IVF according to their own needs and preferences.
