The genetics of blood: A global perspective

Date:
September 4, 2020
Source:
University of Montreal
Summary:
To better understand the properties of blood cells, an international
team has been examining variations in the DNA of 746,667 people
worldwide.



FULL STORY ========================================================================== What's the risk of different human populations to develop a disease? To
find out, a team led by Universite' de Montre'al professor Guillaume
Lettre created an international consortium to study the blood of hundreds
of thousands of people worldwide.


==========================================================================
In one of the largest studies of its kind, published today in Cell,
close to 750,000 participants from five major populations -- European,
African, Hispanic, East Asian and South Asian -- were tested to see the
effect of genetic mutations on characteristics in their blood.

These characteristics include such things as hemoglobin concentration
and platelet counts.

"Each human population is subject to different environments," said Lettre,
a researcher at the Montreal Heart Institute.

"Over thousands of years," he said, "these environmental pressures have resulted in the progressive appearance of variations in DNA, called
genetic mutations, which can influence our physical characteristics, such
as skin size or color, but also our risk of getting certain diseases."
He added: "This observation (of how the environment affects how people's appearance and health vary in different parts of the world) represents
the cornerstone of the theory of evolution by natural selection proposed
by Charles Darwin in 1859." The consortium founded by Lettre and his colleagues chose to study 15 characteristics of blood cells because
previous studies had already uncovered mutations whose consequences were limited to certain populations.



==========================================================================
45 million genetic mutations By testing more than 45 million genetic
variations in each participant, Lettre and his collaborators have
found more than 5,000 mutations in human DNA that affect the blood characteristics of populations around the world.

Done in conjunction with another study focusing exclusively on individuals
of European origin, the new study shows that the vast majority of
mutations associated with blood cells were common to all five major
population groups.

But aside from these, the researchers also found about 100 mutations
whose effect was restricted to certain populations and which, it turns
out, are not found in people of European descent.

For example, in individuals of South Asian origin, the researchers
identified a mutation in the interleukin-7 gene that stimulates the
secretion of this molecule and thus increases the levels of lymphocytes (a
type of white blood cell in the immune system) circulating in their blood.



==========================================================================
"Of course, this kind of mutation can affect the health of people of
South Asian origin," Lettre noted. "It's thought that this mutation could influence their capacity to resist certain infections or develop diseases
like blood cancer." However, he cautioned, "these are, at present,
only hypotheses, as researchers do not have the capacity to test them,
given the immense costs and the difficulty of finding participants for
this type of study." Improving ways of predicting By comparing the
genetic results obtained in each population, the researchers were able
to prioritize certain genes that appear to have an overall effect on
blood cell production.

This will make it possible, over the long term, to improve ways of
predicting the risk of suffering from certain diseases and to develop new,
more effective treatments.

Here again, however, major investments in research will be required
to analyze the consequences of these mutations on the health of these population groups.

Another major obstacle will be to convince researchers how important it
is for all population groups globally to be included in these types of
genetic studies.

"Despite the size of our study, the vast majority of participants --
about 560,000 out of 740,000 individuals -- were of European origin,"
Lettre noted.

"This necessarily introduces a bias into the study." In the future, he
said, "we hope to work with populations that have been little studied
so far -- for example, East African populations or indigenous peoples
- - in order to shed light on new genes that regulate blood cells."
One thing is clear, he concluded: in order to better understand human
diseases and to ensure that everyone, regardless of ethnic origin,
is able to benefit from advances in genetics and precision medicine,
diseases will have to be studied in all populations worldwide.


========================================================================== Story Source: Materials provided by University_of_Montreal. Note:
Content may be edited for style and length.


========================================================================== Journal Reference:
1. Ming-Huei Chen, Laura M. Raffield, Abdou Mousas, Saori Sakaue,
Jennifer
E. Huffman, Arden Moscati, Bhavi Trivedi, Tao Jiang, Parsa Akbari,
Dragana Vuckovic, Erik L. Bao, Xue Zhong, Regina Manansala,
Ve'ronique Laplante, Minhui Chen, Ken Sin Lo, Huijun Qian, Caleb
A. Lareau, Me'lissa Beaudoin, Karen A. Hunt, Masato Akiyama, Traci
M. Bartz, Yoav Ben-Shlomo, Andrew Beswick, Jette Bork-Jensen,
Erwin P. Bottinger, Jennifer A. Brody, Frank J.A. van Rooij,
Kumaraswamynaidu Chitrala, Kelly Cho, He'le`ne Choquet, Adolfo
Correa, John Danesh, Emanuele Di Angelantonio, Niki Dimou, Jingzhong
Ding, Paul Elliott, To~nu Esko, Michele K. Evans, James S. Floyd,
Linda Broer, Niels Grarup, Michael H. Guo, Andreas Greinacher,
Jeff Haessler, Torben Hansen, Joanna M.M. Howson, Qin Qin Huang,
Wei Huang, Eric Jorgenson, Tim Kacprowski, Mika Ka"ho"nen, Yoichiro
Kamatani, Masahiro Kanai, Savita Karthikeyan, Fotis Koskeridis,
Leslie A. Lange, Terho Lehtima"ki, Markus M. Lerch, Allan
Linneberg, Yongmei Liu, Leo- Pekka Lyytika"inen, Ani Manichaikul,
Hilary C. Martin, Koichi Matsuda, Karen L. Mohlke, Nina Mononen,
Yoshinori Murakami, Girish N. Nadkarni, Matthias Nauck, Kjell Nikus,
Willem H. Ouwehand, Nathan Pankratz, Oluf Pedersen, Michael Preuss,
Bruce M. Psaty, Olli T. Raitakari, David J.

Roberts, Stephen S. Rich, Benjamin A.T. Rodriguez, Jonathan
D. Rosen, Jerome I. Rotter, Petra Schubert, Cassandra
N. Spracklen, Praveen Surendran, Hua Tang, Jean-Claude Tardif,
Richard C. Trembath, Mohsen Ghanbari, Uwe Vo"lker, Henry Vo"lzke,
Nicholas A. Watkins, Alan B.

Zonderman, Peter W.F. Wilson, Yun Li, Adam S. Butterworth,
Jean-Franc,ois Gauchat, Charleston W.K. Chiang, Bingshan Li,
Ruth J.F. Loos, William J.

Astle, Evangelos Evangelou, David A. van Heel, Vijay G. Sankaran,
Yukinori Okada, Nicole Soranzo, Andrew D. Johnson, Alexander
P. Reiner, Paul L. Auer, Guillaume Lettre. Trans-ethnic and
Ancestry-Specific Blood- Cell Genetics in 746,667 Individuals
from 5 Global Populations. Cell, 2020; 182 (5): 1198 DOI:
10.1016/j.cell.2020.06.045 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/09/200904090308.htm

--- up 1 week, 4 days, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)