Granted, having twins is indeed a blessing, but that does not undermine the fact that most of our mothers do not even have a reasonably detailed knowledge of the similarities limits of their twins; they are rather understandably carried away with the joy and excitement. For some reason, I strongly believe that you will be gladdened to be enlightened on the true nature of your God-given pair of human beings.
According to John of Nitalks.com or a start, some of us don’t even know the particular type of twins we have, let’s pick it up from there.
Twins, which accounts for over 90 percent of multiple births, are of two types – identical (monozygotic) and fraternal (dizygotic). What’s the difference? Many mothers or women may claim to know about this, but that might not be the case. Many feel that the difference between identical and fraternal twins is their physical resemblance. In actuality, that is not entirely the truth. The reliable reason for the difference between identical and fraternal twins lies in their formation. Identical twins are formed when one fertilized egg (ovum) splits and develops two babies with entirely the same genetic information. However, in the case of fraternal twins, two eggs (ova) are fertilized by two sperm and produce two genetically unique children, who are no more alike than individual siblings born at different times. The reason why some fraternal twins may be mistaken for identical twins can be explained in a daring scientific theory. This theory suggests that there might be a third type of twin. This third type of twins is said to be formed when the egg splits in two, and each half is then fertilized by different sperm, resulting in an intense resemblance in the twins conceived. It doesn’t end there you know.
Now you are knowledgeable enough to discern if your twins are actually identical or fraternal, it’s high time we discovered how much your twins — identical or fraternal respectively – have in common. Let’s start with the identical twins. It might be mind-blowing to know that your twins despite being said to be identical have some differences, regardless of their supposedly matching genes.
- Differences in environmental impact
Right from the early environment in the womb, external influences can change the appearance of twins. For instance, while some identical twins may share a placenta, one twin may have a more advantageous connection to the placenta, receiving the first turn of nutrients. This can lead to a size variance between babies which continue as they grow up. Like every other human, there are many circumstances that create differences in the twin’s appearances, personalities, and interests individually, especially as the twins approach the teen years.
- Epigenetic Differences
To understand this aspect of their differences better, we need to get it straight with the word, ‘epigenome’. The epigenome refers to natural chemical modifications within a person’s genome (genetic material). A well-founded study concluded that, though identical twins are born with the same epigenome, their epigenetic profiles begin to diverge as they age and spend more time apart. Scientist offered two theories to explain this phenomenon. They are respectively, that epigenome marks are removed randomly as people age, and environmental influences change the pattern of epigenetic marks. Changes in the epigenome may be responsible for the development of diseases, like cancer.
- Differences in a DNA sequence
Further research shows that identical twins are not actually identical. A reliable researches challenge the accepted notion that identical twins have identical genetic profiles. In the course of this research, changes we have seen in the DNA sequence between identical twins which were seen to reflect in Copy Number Variations. What is not certain inline with this research is whether these changes occur during fetal development or as twin’s ages
As for fraternal twins, apart from the established fact that they no more alike than individual siblings born at different times, there are some other facts you need to know about them, such as;
- They might be of different or the same gender.
- They may or may not look alike.
- They can run in families.
- They can be conceived at different times by different fathers.
- They can be as a result of fertility treatment.
- They can be affected by pregnancy factors.