(CNN) It was an all-male lineup of laureates for last year's Nobel Prizes in medicine, physics and chemistry, awards which grant the recipients entry to the most prestigious club in science.
That none of the 2021 winners in those categories were female was, for some critics, more evidence of systemic bias in science, with women already less likely to be given credit or named as lead author on scientific papers despite more and more women participating in scientific research.
However, others say last year was a blip in a broadly positive trend, pointing to a lag effect that results from the Nobel committee typically honoring advances that happened three or four decades ago, when there were fewer women in senior positions in scientific fields.
David Pendlebury, a senior analyst at Clarivate, analyzes how often a scientist's key papers are cited by peers, which he says is an indicator of whether a person will win a Nobel Prize.
"Two decades ago it would be rare than I would find a woman, for example, to designate as a citation laureate, but as we move forward in time, we find there are more women... in the top ranks of researchers," he said ahead of the 2022 Nobel Prize announcements next week. A citation laureate is someone considered likely to win a Nobel Prize. "That's why I say it's inevitable that the Nobel Prize is going to be given to more and more women.. and it will be geographically more diverse."
In 2020, two women, Emmanuelle Charpentier and Jennifer A. Doudna, won the Nobel Prize in chemistry, for the development of the CRISPR method for genome editing, while Andrea Ghez was part of a trio that won the Nobel Prize in physics for the discovery of a supermassive blackhole. Winners in 2019, when the Nobel committee asked nominators to consider diversity in gender, geography and field, were all men, while 2018 saw the first female winner for physics since 1963, Donna Strickland.
It's notoriously tricky to predict who will win a Nobel Prize, an honor established by Swedish industrialist Alfred Nobel more than a century ago. The short list is secret, as are the nominators, and documents revealing the details of the selection process are sealed from public view for 50 years. However, there's no shortage of worthy female candidates to be the next science laureates. Here are five female scientists and the life-changing discoveries they have made.
Cancer-causing genes: In the 1970s, while it was understood that cancer sometimes ran in families, cancer research was focused on viruses. With a background in researching the genetic differences between humans and chimpanzees, Dr. Mary-Claire King, now a professor of medicine and of genome sciences at the University of Washington School of Medicine, took a fresh approach. She discovered the role a mutation of the BRCA1 gene played in breast and ovarian cancer. The discovery has enabled genetic testing that can identify women who are at increased risk of breast cancer, as well as steps to reduce their risk, such as additional screening and preventive surgeries.
Vaccine breakthrough: Dr. Katalin Karikó, a senior vice president at BioNTech based in Germany, won a 2021 Lasker award, an honor which is often seen as a precursor to the Nobel prize. Along with Drew Weissman, a professor in vaccine research at the University of Pennsylvania, she pioneered a method of using synthetic messenger RNA to fight disease that involves changing the way the body produces virus-fighting material. While their paper received little attention when first published in 2005, their research is now the basis of two widely used Covid-19 vaccines.
Astronomical curiosity: Jocelyn Bell Burnell, a physicist from Northern Ireland, contributed to the discovery of the pulsar, a puzzling astronomical phenomenon, as a postgraduate student at Cambridge University. However, it was her supervisor Antony Hewish, who shared the Nobel Prize in physics in 1974, who got credit for the discovery. In interviews, Bell Burnell has been magnanimous about being overlooked, saying she was proud the stars she observed had convinced the prize committee. "My contemporaries were more upset about the Nobel than I was not to be recognised. One of them labelled it the 'No-Bell' prize!" she said in an interview. In 2018, she was awarded a Special Breakthrough Prize in Fundamental Physics, for which she received 2.3 million pounds. She donated the money toward helping people from underrepresented groups become physicists.
Revolutionary chemistry: Dr. Carolyn Bertozzi, a professor at Stanford University, has pioneered a new field called bioorthogonal chemistry, which focuses on chemical reactions within living cells that can be conducted without interfering in innate cellular processes. She sought to understand why cells are coated in sugar and how these sugar molecules contribute to conditions such as cancer, inflammation and bacterial infection. Modifying these cells through biorthogonal chemistry has led to new ways to treat many diseases. She won this year's Wolf Prize for chemistry and is also an active campaigner for LGBT rights.
Preventing sickle cell disease: Dr. Marilyn Hughes Gaston dedicated much of her life to understanding sickle cell disease, an inherited condition in which the body is unable to produce normal hemoglobin. Affecting children, it results in tissue damage, causing weakness and even death. Gaston became interested in the condition while interning at Philadelphia General Hospital in 1964. In 1986, she published the results of a groundbreaking national study that proved the effectiveness of giving children with sickle cell disease long-term penicillin treatment to prevent septic infections resulting from the disease. As a result of Gaston's work, every child is screened for sickle cell disease at birth. She was also the first African American to direct the US Bureau of Primary Health Care.
The Nobel Prize in physiology or medicine will be announced on Monday, followed by the physics prize on Tuesday and the Nobel Prize in chemistry on Wednesday. The Nobel Prize for literature and the Nobel Peace Prize will be announced on Thursday and Friday, respectively.