The term "designer babies" is used to describe how genetic technologies can be used to choose the sex, eye color, hair color, and other characteristics of a child. Also called genetic engineering, designing a baby opens up many possibilities as well as ethical dilemmas. It is a controversial topic, and the technologies behind designing babies has the potential to alter the human race.

DNA holds the blueprint of an organism's individual characteristics. The segments of DNA that control certain features are called genes. Using certain types of enzymes, scientists have been able to cut specific genes and use them to create customized strands of DNA. These strands can then be inserted into an embryo to alter the organism's genetics.

The rapid advances in knowledge of human DNA and the ability to modify it has led to the possibility of creating designer babies. Currently, basic types of genetic screening and alteration are possible. Fertility doctors already can use genetic screening and in vitro fertilization (IVF) to select fertilized embryos according to gender. They can also check genes for certain abnormalities or potential future hereditary diseases, such as diabetes or cancer. In some cases, doctors can use IVF and genetic modification to create designer babies using only healthy, normal genes.

Although the potential for using genetic engineering for the good of the human race is an exciting prospect, the technology also has many downsides, according to critics. Opponents of using genetic alteration to create designer babies say that it could produce a race of super children, but only to people who can afford the necessary procedures. This could increase societal inequalities. Also, the modifications made to the DNA of designer babies permanently alters the child's genetics, and those changes are passed on to future generations. Over time, this could irreversibly change the human species.

Most opponents of genetic modification are not too worried about the ability to choose a baby's sex or eye color, but are worried that it will lead to more and more genetic interference. Many religious groups oppose the technology, stating that people should accept the children God gives them. Some countries have outlawed the use of genetic alteration in humans. Others are trying to come up with laws that allow certain types of genetic screening and modification that relate to disease prevention, while making other types of genetic interference illegal.