We all know that the man's genetic information determines the sex of the child, but what else does a person's genes establish? Here are some interesting facts on genetics: Identical twins share 100% of their genetic markers, and no genetic test can distinguish them! In situations where it is unclear which twin impregnated a woman, fatherhood cannot be established. Watch out for twins! If all the DNA contained within the cells of one human being were stretched out, it would reach to the Moon and back eight thousand times! Chimps share 98% of their genes with humans. Using a sperm-sorting machine, doctors have developed a system that allows couples to choose the sex of their baby in advance. Genetic engineering of today gives couples a 75% chance of selecting the sex of their baby, compared to nature's 50/50. Within a decade or two, it may be possible to determine a child's height, hair and eye color, IQ and personality type before he or she is even conceived!