Findings could lead to new clinical laboratory tests to screen for individuals with increased risk of blood transfusion complications
Pathologists and clinical laboratory scientists who understand the complexities of blood typing from one human to another will be interested to learn that a 50 year-old mystery has brought about an exciting new discovery—a new human blood group.
British and Israeli scientists led by the UK’s NHS Blood and Transplant (NHSBT) and the University of Bristol discovered the meaning behind a missing protein molecule found in a pregnant woman five decades ago. This anomaly has now been given its own blood group identification called MAL, according to a University of Bristol new release.
“Some people can lack this blood group due to the effect of illness, but the rare inherited form of the AnWj-negative phenotype has only been found in a handful of individuals—though due to this discovery it will now be easier to find others in the future,” the news release notes.
This is important because receiving mismatched blood can be fatal.
“AnWj is a high-prevalence red blood cell (RBC) antigen in the ISBT 901 series. Only nine reports of anti-AnWj have been published since it was first documented in 1972,” according to a 2012 article published by the American Association of Blood Banks, now known as the Association for the Advancement of Blood and Biotherapies (AABB).
For even the small proportion of the population with this new blood group, diagnosing its presence can have a major impact while preventing unwanted harm.
“The work was difficult because the genetic cases are very rare. We would not have achieved this without exome sequencing, as the gene we identified wasn’t an obvious candidate and little is known about Mal protein in red cells,” said Louise Tilley, PhD, Senior Research Scientist, IBGRL Red Cell Reference at NHS Blood and Transplant, in the news release.
“The genetic background of AnWj has been a mystery for more than 50 years, and one which I personally have been trying to resolve for almost 20 years of my career,” said Louise Tilley, PhD (above), Senior Research Scientist, IBGRL Red Cell Reference at NHS Blood and Transplant, in the news release. “It represents a huge achievement, and the culmination of a long term effort, to finally establish this new blood group system and be able to offer the best care to rare, but important, patients,” she added. Clinical laboratory scientists involved in blood banking will want to keep updated as further research into this new blood group is published. (Photo copyright: NHS Blood and Transplant.)
Unraveling the Mystery
In 1972, scientists were stumped by a pregnant woman with a blood sample that was “mysteriously missing a surface molecule found on all other known red blood cells at the time,” Science Alert reported. The AnWj antigen that was missing in that patient’s blood is present in 99.9% of human blood samples.
“Researchers found that the AnWj antigen is carried on the Mal protein. While illness can cause some people to lose the AnWj antigen, inherited cases of the AnWj-negative phenotype are extremely rare. Using whole exome sequencing on five genetically AnWj-negative individuals, researchers confirmed that, in these cases, the participants lacked the antigen due to homozygous deletions in the MAL gene,” an AABB news release stated.
The researchers named the group with the missing antigen the MAL blood group (short for Myelin and Lymphocyte Protein) which is where the antigen resides.
Genetic sequencing enabled the scientists to locate the gene when they “inserted the normal MAL gene into blood cells that were AnWj-negative. This effectively delivered the AnWj antigen to those cells,” Science Alert noted.
Mutated MAL genes result in the AnWj-negative blood type. The team discovered three patients with the blood type and no mutation, “Suggesting that sometimes blood disorders can also cause the antigen to be suppressed,” Science Alert added. The researchers also discovered that AnWj isn’t present in newborns but arrives sometime after they are born.
“Interestingly, all the AnWj-negative patients included in the study shared the same mutation. However, no other cell abnormalities or diseases were found to be associated with this mutation,” Science Alert said.
The discovery that “the Mal protein is responsible for binding AnWj antibodies” could lead to new clinical laboratory tests to screen for patients at risk from blood transfusions, AABB noted in its news release.
Facing the Challenge
Scientists had to overcome many challenges to uncover the details of this blood type. The complexity of the protein further hindered their efforts.
“MAL is a very small protein with some interesting properties which made it difficult to identify, and this meant we needed to pursue multiple lines of investigation to accumulate the proof we needed to establish this blood group system,” said Tim Satchwell, PhD, senior lecturer and cell biologist at the University of the West of England, in the University of Bristol news release.
“Resolving the genetic basis for AnWj has been one of our most challenging projects,” Nicole Thornton, head of IBGRL Red Cell Reference at NHSBT told the AABB. “There is so much work that goes into proving that a gene does actually encode a blood group antigen, but it is what we are passionate about, making these discoveries for the benefit of rare patients around the world.”
It’s hard to pinpoint how many individuals will benefit by testing for the blood group, Tilley told the BBC. Nevertheless, “the NHSBT is the last resort for about 400 patients across the world each year,” the BBC reported.
While more research needs to be done, the initial discovery is promising and may lead to new clinical laboratory tests to identify individuals who could be severely harmed should they receive the wrong blood type during a transfusion.
Wait times blamed on the Irish National Health System’s ‘overstretched’ services and ‘under-resourced’ commitment to cancer genetic testing done by medical laboratories
Histopathologists in the UK and anatomic pathologists in the US understand the important role predictive genetic testing can play in helping patients understand their risk for certain types of breast, bowel, and ovarian cancers. While timely access to cancer testing may be routine in the United States, a report out of Ireland reveals patients in that country’s government-run healthcare system may have to wait up to two years or more for genetic counseling and testing.
UK Patients in Need of Genetic Services Are Switching from Public to Private Healthcare
While early access to genetic testing can provide opportunities for preventative treatments or earlier diagnosis of cancer, many patients in Ireland with a family history of cancer must wait months or years for genetic services. UCC Nursing Professor and Physiologist Josephine Hegarty, PhD, lead author of the ICS report, stated in a news release that “public cancer genetic services are overstretched. Waiting lists exist at every point on the pathway for people who need genetic services.”
She added, “Many patients spoken to seemed to abandon the waiting for overstretched public services in favor of paying for private testing and treatment.”
While the ICS report’s survey sample size was small—154 patients, family members, or members of the public—the data revealed:
One in seven respondents waited 13-24 months and one in 27 waited over 24 months for counseling and testing appointments.
Many people had changed from the public health system to private healthcare to speed up access to genetic testing.
The cumulative waiting time from referral to counseling, testing, receipt of genetic test results, and onwards to screening, surveillance, or prophylactic treatments [aka, preventive healthcare] can be up to four years, which patients see as time lost in terms of cancer prevention and early intervention.
Barriers to Genetic Services Affect Treatment Decisions
A separate survey of 52 healthcare professionals highlighted barriers for accessing services with six in 10 respondents saying they are under-resourced and four in 10 concerned about access to follow-up surgery for patients deemed to be at high risk.
In the ICS news release, breast cancer patient Margaret Cuddigan said genetic testing was not available to her at diagnosis.
“In those 13 months waiting for a result, I went through chemotherapy, a lumpectomy, and radiotherapy on my breast, only for a double mastectomy to be required once the BRCA mutation was known. Had I known this earlier, my course of treatment could have been very different,” Cuddigan said.
“I had to postpone a radiation treatment to go up to Dublin from Cork to do the genetic test, as it would have taken up to another 12 months in Cork, and then I waited over four months for the results. Once I received the news of the gene mutation, I had to navigate a path of risk-reducing surgeries,” she noted, adding, “I researched and sought out a surgeon myself.”
Long Waits for Genetic Testing Are Common in Single-Payer Healthcare
The waiting list for genetic cancer testing has long been an issue in Ireland. A 2017 article in the Irish Examiner, titled, “Woman Faces 18-month Wait for Vital Cancer Test,” brought to light the 18-month waiting time for BRCA1 and BRCA2 mutation testing for breast cancer. While the COVID-19 pandemic has further exacerbated the backlog of cancer treatment services, such issues are not new in single-payer healthcare systems.
Across the Irish Sea in Great Britain, some patients have experienced delays of six months before getting cancer test results. In “Shortage of Histopathologists in the United Kingdom Now Contributing to Record-Long Cancer-Treatment Waiting Times in England,” Dark Daily reported how prolonged wait times for cancer test results in the United Kingdom’s National Health Service are one disadvantage of a government-run, single-payer health system. With limited funds, frequently the government health program under invests in certain clinical services. It is not until several years later that the underinvestment reveals itself in the form of lengthy wait times.
Meanwhile, it is cancer patients and their families who pay the price for underinvestment because delays in their cancer test results then delay timely treatment decisions. This is particularly true when an immediate start of therapy for an aggressive form of cancer is imperative.
ICS Executive Director, Advocacy and External Relations, Rachel Morrogh, argues the solution is prioritizing cancer prevention within the Health Service Executive, which runs Ireland’s national healthcare system.
“The reality is the focus must be on urgent care, but we’re missing chances to keep people healthy (through genetic testing),” Morrogh told the Irish Independent. “We can prevent four in 10 cancers, but we have to prioritize prevention. There needs to be a significant investment and the expansion of capacity across all the follow-on services that someone with a genetic risk of cancer may need, focusing on the development of a dedicated and resourced pathway for them.
Irish Cancer Society’s Director of Advocacy and External Affairs Rachel Morrogh (above left with Donal Buggy, Director of Services, Delivery and Innovation at ICS) maintains that “Patients [in the Irish healthcare system] need a dedicated group of multi-disciplinary doctors following them so that they can be offered options and psycho-oncology support when they need it.” She added, “The government must now listen to patients and those working in our hospitals and provide more resourcing and staffing.” (Photo copyright: Irish Examiner.)
The ICS report found that limited access to timely genetically-guided health and oncology services is the result of multiple barriers to care.
“It is apparent from engaging directly with service users that waiting lists exist at every point on the pathway for people who need genetic [cancer testing] services,” the report states. “For those who may have a genetic risk of cancer, the wait times for access to [genetic cancer] testing alone (before counselling treatment, prophylactic surgery, etc.) can be up to two years. Barriers to accessing cancer genetic services include costs of tests, long processing time for referrals to tests, restrictive referral criteria, and difficulty in accessing information on cancer genetic services.”
In the forward she wrote for the ICS report, ICS Chief Executive Officer Averil Power said her organization would continue its push for improved access to genetic testing services. “Government needs to not only expand capacity for testing and counselling, but also ensure that the follow-on services that are needed by people diagnosed with a genetic risk of cancer are in place and can be accessed swiftly.”
The ICS report is another reminder to histopathologists in the UK—as well as anatomic pathologists in the US—that a single-payer healthcare system comes with its own flaws and access-to-care issues.
