Never before has there been a worldwide mapping of blood group
genes in healthy individuals. Most previously known blood group variants
were discovered when a blood transfusion failed, i.e. when it didn't
work between the donor and the recipient.
1,000 new mutations in the blood group genes: that is what physician
and former programmer Mattias Möller found in his research study in
which he developed new software and investigated blood group genes in
2,504 people. This discovery from Lund University in Sweden was published
recently in the journal Blood Advances
‘1,000 new mutations in the blood group genes have been observed by physician and former programmer Mattias Möller in his research study.’
Genomes from 2,504 people
The international project 1,000 Genomes is so far the world's largest
mapping of human genetic variants. By creating a new computer program,
Mattias Möller processed the genomes of 2,504 people. He imported these
genomes to his newly developed database Erythrogene, and matched them
against previously known genetic variants. The result was the discovery
of 1000 hitherto unknown mutations which could have a negative effect
in the case of blood transfusions, for example.
"I started from the genes
instead, to find variations in DNA which might give rise to a new
antigen*, likely to cause problems in case of transfusion, for example",
explains Mattias Möller, doctoral student at the Department of
Mismatch can lead to death
On the surface of the red blood cells are proteins and sugar
molecules, in which small differences give rise to different antigens.
The ability to identify and match blood group types is important for
blood transfusions, but also in pregnancy and before certain types of
A transfusion with mismatched blood can lead to a
transfusion reaction. This type of reaction can be mild and barely
noticeable, or so strong that the blood cells rupture and, in the worst
cases, the patient dies.
Mattias Möller's study showed that 89% of the genetic
variants were previously known, but among the remaining 11% were
a total of 1,000 different mutations which were absent from official
catalogues of known blood group variants.
"Of course not all variants lead to new antigens. But we need to go
on and conduct further analyses to investigate how the genetic
expression changes, i.e. how the molecules on the surface of the cell
Undiscovered antigens in Africa
There are currently 352 mapped antigens, but the research has so far
mainly focused on populations in Europe and North America. A future
research field is Africa, where there is greater variation between
different population groups. As research on African populations
increases, in combination with blood transfusions becoming more common
there, many new antigens are likely to be discovered.
"The new online database enables researchers to study a specific
blood group and see where in the world it occurs. It has been incredibly
exciting to combine my knowledge as a programmer and researcher to
design this database in a format which is easy to use in transfusion
medicine. Now researchers can dig deeper into the results, and it is
also easy to extend the database with other genes responsible for human
disease or data from new major genetic mapping projects", concludes
An antigen is a part of a molecule which can have various functions
on the surface of the cell, such as transporting necessary nutrients or
signalling. Different individuals express different antigens, and if
cells with a certain antigen are transferred to a person who does not
have the same, which can happen in the case of transfusion or
transplant, this can cause an immune reaction, such as rapid breakdown
of red blood cells or rejection of the transplanted organ.
The 1000 Genomes project was completed in 2015 and provides the
largest public catalogue of human genetic variation in the world so far.