✔ 最佳答案
They are ALMOST completely identical, but keep in mind that DNA replication in humans produces about 1 error per billion base pairs, so the first replication of the fertilized egg will probably contain on average 3 mutations. Furthermore, each generation of somatic cells is subject to a similar mutation rate, so that if you take one cell from the same tissue of each twin and sequence the DNA, there are perhaps hundreds of differences. However, hundreds of differences is pretty much nothing compared to the 3-billion-odd base pairs in the entire human genome, especially considering that most of these differences will occur in non-coding segments of DNA.
參考: 15 years experience in biological science.