03-01-2019, 02:01 PM
I found this article extremely fascinating as well! From the information I previously learned in Biology 30 regarding the fertilization of an ova and fetal development I was completely unaware that an event like this could occur. After reading the article, I was interested on how it was possible that two separate sperm cells could fertilize a single egg and result in semi-identical twins. With further research I came across another article about the first recorded case of semi-identical twins. This article ( http://content.time.com/time/health/arti...99,00.html ) proposes two scenarios in which this type of fertilization could have occurred. The first being that the a single egg could have divided before fertilization occurs, this would how ever contradict what we learned in Biology class because the egg is not supposed to divide until fertilization has happened. The other more likely scenario would have been that the egg was fused with two sperm cells and created a triploid cell. During the second-cell stage the gg would then shed the chromosomes from each of the sperm in order to self-correct it's chromosomal count. Overall, a very interesting and rare case.