Overview

Imagine a world where parents can choose the genetic makeup of their babies and give them special traits through genetic engineering. In theory, these traits can vary from lower resistance to diseases to even gender selection. In a way, designer babies are already here, and their significance to the future of healthcare is already shaping modern pregnancies.

The science and other stuff to know

The term “designer baby” refers to a baby that has been given special traits through genetic editing. This is usually done by altering the genes of the egg, sperm, or embryo. These traits can vary from lower resistance to diseases to even gender selection.

The procedure can entail analyzing a large number of human embryos to discover genes associated with specific diseases and features and then selecting embryos with the desired genetic composition, which is known as preimplantation genetic diagnosis. While single gene screening is prevalent, polygenic screening is offered by only a few businesses, and directly editing the genome before birth has only occurred once as of this writing, when Chinese twins Lulu and Nana were edited as embryos, causing worldwide controversy and ethical outrage. Biologist He Jiankui, who unveiled his creation of genetically engineered babies at a Hong Kong seminar, was imprisoned in China for the act.

Designer babies are made possible through in vitro fertilization (IVF). They are achieved either by removing small sections of the existing genome or by introducing new segments of DNA into the genome. A new procedure called CRISPR allows scientists to cheaply and rapidly alter the genome of almost any organism.

“I do not love the term ‘designer babies’ because it is imprecise. [In one sense], they are already here and have been for a long time,” says Glenn Cohen, Harvard Law School Faculty Director and a leading expert in bioethics and law. “When [individuals] consider the need to use a sperm donor for artificial insemination… they engage in a form of trait selection.”

“The catalogs that feature sperm ‘donors’ (donors in scare quotes because they are paid) recruited for sperm banks have already excluded 99% of applicants, and who is left tends to have very desirable health, intelligence, and beauty traits. The same is true for egg donors. So already parents using these technologies are ‘designing’ their babies,” he added.

For instance, in 2017, a group of scientists announced that they had successfully edited a human embryo to eradicate a heart condition.

So what?

While gene editing in humans remains a controversial topic, not all forms of human genetic manipulation are in question. For instance, it could be used to alter cells in the body’s immune system in order to target and destroy cancer cells or to replace the genes that cause sickle cell anemia with non-sickle cell genes.

The only issue with genetic editing arises when there are no limits. Typically, gene editing can be performed on both somatic cells and stem cells. Altering somatic cells, which are cells in the body other than sperm and egg cells, for the treatment of a particular disease or illness isn’t generally controversial.

However, editing stem cells, which are special cells that have the ability to develop into many different cell types, is illegal in the United States and many other countries. And even where it’s not illegal, it’s in contravention of research guidelines, as well as moral and ethical standards. This is primarily because altering one gene in a stem cell may lead to unintended effects on other genes.

What’s next?

While the intricacies of designer babies may sound like the plotline of a science fiction movie, it has been a real part of modern science for quite some time. Gene-editing technologies are currently being applied in mammalian cells and whole animal models to understand how gene variations are linked to disease. This demonstrates the potential for this technology to be used to investigate and treat human diseases.

In the future, this tech could potentially be applied to other diseases based on single gene mutations, including Huntington’s disease, cystic fibrosis, sickle cell anemia, and Tay-Sachs disease.

However, designer babies certainly raise serious safety and ethical concerns. The primary concern is that any changes to DNA could become a permanent part of the human genetic blueprint. And if scientists were to make a mistake, they could introduce a new disease that could be passed down to future generations.

As genetic technology advances, we may be on the verge of a slippery slope. Many scientists, ethicists, and legislators fear a future in which babies are genetically designed for features that have little to do with preventing deadly medical disorders, such as athletic prowess, eye color, and I.Q.