Biggest Scientific Breakthroughs in Animal Research in 2021

If you’re looking for updated content, we’ve created a new post on scientific discoveries and breakthroughs for the last year.

This past year was a big one for scientific research, with breakthroughs coming in everything from vaccines for chronic diseases to new approaches to extending lifespan. Here are 2021’s biggest scientific breakthroughs in studies with mice.

January: A Vaccine for Multiple Sclerosis

Using the same mRNA technology used to develop its COVID-19 vaccine, German biotechnology company BioNTech developed a prospective vaccine for multiple sclerosis that has shown excellent results in mouse models. The treatment delays the onset of the disease and reduces the severity of symptoms, without the immune suppression effects found in current treatments. Learn more.

February: Repairing Damaged Livers

More than 12,000 people in need of a liver transplant are currently on the national waiting list for a liver from a deceased organ donor. Animal research has already made huge strides in immunosuppression, which reduces organ rejection, and now a study with mice has shown that bile ducts grown in a lab from stem cells can be used to repair damaged human livers, which could eliminate the need for a transplant. Learn more.

March: A Pill for Parkinson’s

Yumanity Therapeutics developed an orally administered treatment called YTX-7739 that was found to improve motor skills and lessen toxic protein clumping in a mouse model of Parkinson’s. The drug is now in phase 1 clinical trials and has shown good results in people with mild to moderate disease. Phase 2 clinical trials could begin in early 2022. Learn more.

April: Uncovering the Biological Roots of Psychosis

Researchers at Washington University developed a way to induce sound hallucinations in mice, which could help scientists understand the brain circuits that are activated in people with mental disorders including schizophrenia and psychosis. Learn more.

May: Blocking Cancer from Metastasizing

A team of researchers at the University of Chicago, the University of São Paulo, the University of North Carolina, and the University of Texas Southwestern Medical Center discovered that low doses of a four-drug combination can prevent the spread of cancer without triggering drug resistance or recurrence. Learn more.

June: Extending Lifespan by 30%

With a single genetic modification, scientists in Israel were able to extend the life expectancy of mice by 30%—and not only did they live longer, the long-lived mice stayed healthier than their normally aged counterparts. If the treatment is similarly effective in humans, it would increase the average human lifespan to almost 120 years. Learn more.

July: Ability to Control the “Feel-Good” Chemical

Researchers at the University of California San Diego found that mice can control dopamine, the “feel good” neurotransmitter that is related to pleasure and rewards. Rather than relying exclusively on external stimuli, they discovered that mice can control dopamine pulses. Learn more.

August: A Link Between Gut Health and Aging

In yet another major discovery regarding the link between the gut and the brain, a study found that introducing the microbiota of young mice into the intestines of older mice via fecal transplant resulted in improved cognitive function and behavior in the older mice. Learn more.

September: Preventing Cardiac Arrest & Stroke

The antioxidant drug cysteamine, which has already proven safe for human use, may help reverse atherosclerosis, a buildup of fatty deposits along the artery walls that often leads to heart attacks and strokes. A study from the University of Reading in the U.K. showed a 32% to 56% reduction in the size of atherosclerotic plaques in mice treated with cysteamine. Learn more.

October: An Oral Antiviral Treatment for COVID-19

Merck and Ridgeback Biotherapeutics developed the first effective drug treatment for COVID-19. Called molnupiravir, the oral antiviral drug can keep COVID-19 symptoms from worsening and enable a quicker recovery. In clinical trials, molnupiravir reduced the risk of hospitalization or death by approximately 50%. Molnupiravir received FDA emergency use authorization on November 30. Learn more.

November: An Injection That Reverses Paralysis

Researchers at Northwestern University have developed a new therapy that has reversed paralysis and repaired severe spinal cord injuries in mice. After only a single injection of the gel treatment, paralyzed mice regained the ability to walk within four weeks. Learn more.

December: Omicron Does Less Damage to Lungs

In a rare bit of COVID-related good news, a group of scientists in the United States and Japan released a new study showing that the new omicron variant, first identified in South Africa in November, is less damaging to lungs than previous strains. Working with mice and hamsters, the researchers saw less infection in the bronchial cells of hamsters and a smaller amount of the virus in the noses of mice than with previous strains. The initial finding seems to confirm what is being seen in humans with omicron—a variant that while highly contagious, results in milder illness. Learn more.

As we start a new year, we send our thanks to all the researchers, scientists, academic institutions, support staff, and laboratory personnel whose work and dedication made these important breakthroughs, and many more, possible last year. We look forward to what 2022 will bring!