AUG 03, 2017 6:36 PM PDT

Scientists Achieve Very First Safe Repair of Disease-Causing Mutation in Human Embryos

WRITTEN BY: Kara Marker

Using in vitro fertilization (IVF), scientists are introducing genetic editing machinery into egg and sperm cells to prevent mutations that cause dangerous heart conditions. After ensuring the process is safe and effective, they could ultimately begin preventing all disease-causing mutations from being passed on for all future generations.

Scientists have, for the first time, corrected a disease-causing mutation in early stage human embryos with gene editing. The technique, which uses the CRISPR-Cas9 system, corrected the mutation for a heart condition at the earliest stage of embryonic development so that the defect would not be passed on to future generations. Credit: Salk Institute

The current study, published in the journal Nature, focused on a rare heart condition, hypertrophic cardiomyopathy (HCM), which is responsible for the majority of sudden death cases in otherwise healthy young athletes. HCM is caused by a dominant gene mutation in the MYBPC3 gene. And for someone living with the condition, they have a 50 percent chance of passing it down to their children.

From the Salk Institute and collaborators from Oregon Health and Science University (OHSU) and Korea's Institute for Basic Science, scientists incorporated the CRISPR-Cas9 system into their new gene editing strategy. Using induced pluripotent stem cells created from a skin biopsy, donated by a person with HCM, they programed the Cas9 enzyme to “cut” the mutated gene like a pair of molecular scissors. Most importantly, the gene editing tool was designed to leave all other genes alone.

After the mutated gene was cut, the host cells then repaired the DNA like they would any other piece of broken genetic material. Next, researchers injected the gene editing tools into donor eggs and sperm via IVF to see if the process effectively preventing the mutation from being passed on to the embryo.

They analyzed the embryos that developed, observing the handy work of the cells’ DNA repair mechanisms. The new gene editing strategy appeared to be safe (all other genes were untouched) and effective (researchers saw embryos developed that contained no sign of the MYBPC3 mutation).

“Even though the success rate in patient cells cultured in a dish was low, we saw that the gene correction seems to be very robust in embryos of which one copy of the MYBPC3 gene is mutated," explained Jun Wu from the Salk Institute. "Our technology successfully repairs the disease-causing gene mutation by taking advantage of a DNA repair response unique to early embryos.”

Given the high stakes of this particular situation, where one wrong change - even if unintended - could lead to the malformation or death of the embryo, the study researchers stress that this study is just the beginning of many more experiments that will have to be done to ensure the procedure’s safety.

"Thanks to advances in stem cell technologies and gene editing, we are finally starting to address disease-causing mutations that impact potentially millions of people," said Juan Carlos Izpisua Belmonte from the Salk Institute. Izpisua Belmonte is also on the committee for human gene editing with the National Academies of Sciences, Engineering and Medicine. "Gene editing is still in its infancy so even though this preliminary effort was found to be safe and effective, it is crucial that we continue to proceed with the utmost caution, paying the highest attention to ethical considerations."

The current study is “fully compliant” with recommendations from the 2016 report “Human Genome Editing: Science, Ethics, and Governance.

Going forward, Wu, Izpisua Belmonte, and the rest of the research team will work on improving in vitro fertilization (IVF) outcomes and ensuring the safety of this new procedure, with hope that in the future, this gene editing strategy could cure more diseases caused by single-gene mutations.

Source: Salk Institute

About the Author
  • I am a scientific journalist and enthusiast, especially in the realm of biomedicine. I am passionate about conveying the truth in scientific phenomena and subsequently improving health and public awareness. Sometimes scientific research needs a translator to effectively communicate the scientific jargon present in significant findings. I plan to be that translating communicator, and I hope to decrease the spread of misrepresented scientific phenomena! Check out my science blog: ScienceKara.com.
You May Also Like
MAR 12, 2020
Cardiology
MAR 12, 2020
Skipping Breakfast Increases Risk for Heart Disease Death by 87%
According to the old adage, ‘breakfast is the most important meal of the day’. But is that really so? Now, r ...
MAR 23, 2020
Cardiology
MAR 23, 2020
Eating Tofu and Chickpeas Lowers Risk of Heart Disease
New research has found that eating tofu and other foods rich in isoflavones such as chickpeas and peanuts may lower one& ...
APR 05, 2020
Cardiology
APR 05, 2020
Fatter Thighs May Help Stave off Heart Disease
New research has found that a larger thigh circumferences, or ‘fatter thighs’ may be linked to lower blood p ...
APR 06, 2020
Cardiology
APR 06, 2020
Positive Effects of Most Popular Diets Disappear After a Year
While evidence suggests that most diets lead to similar modest losses in weight and improvements in cardiovascular risk ...
MAY 06, 2020
Cardiology
MAY 06, 2020
Can Alcohol Consumption Increase Your Risk of Peripheral Arterial Disease?
Peripheral Arterial Disease (PAD) is a chronic disease where plaque builds up in the arteries in the legs. This buildup ...
MAY 11, 2020
Cardiology
MAY 11, 2020
Urbanization and Cardiometabolic Risk
A recent study by the Barcelona Institute for Global Health (ISGlobal) was first to analyze the possible connection betw ...
Loading Comments...