Genome-wide association study of erythrocyte density in sickle cell disease patients.

Pubmed ID: 28552477

Journal: Blood cells, molecules & diseases

Publication Date: June 1, 2017

Affiliation: Faculty of Medicine, Program in Bioinformatics, Université de Montréal, Montreal, Quebec, Canada; Montreal Heart Institute, Montreal, Quebec, Canada. Electronic address: guillaume.lettre@umontreal.ca.

MeSH Terms: Humans, Male, Adult, Female, Alleles, Polymorphism, Single Nucleotide, Anemia, Sickle Cell, Genome-Wide Association Study, Genotype, Young Adult, Genetic Variation, Erythrocytes, Erythrocyte Indices, Hemoglobin, Sickle, Quantitative Trait Loci, Plasma Membrane Calcium-Transporting ATPases

Grants: MOP123382, MOP3251163

Authors: Brugnara C, Lettre G, Ilboudo Y, Galactéros F, Bartolucci P, Rivera A, Sedzro JC, Beaudoin M, Trudel M, Alper SL

Cite As: Ilboudo Y, Bartolucci P, Rivera A, Sedzro JC, Beaudoin M, Trudel M, Alper SL, Brugnara C, Galactéros F, Lettre G. Genome-wide association study of erythrocyte density in sickle cell disease patients. Blood Cells Mol Dis 2017 Jun;65:60-65. Epub 2017 May 13.

Studies:

Abstract

Deoxy-hemoglobin S polymerization into rigid fibers is the direct cause of the clinical sequelae observed in sickle cell disease (SCD). The rate of polymerization of sickle hemoglobin is determined primarily by intracellular hemoglobin concentration, itself dependent on the amount of sickle hemoglobin and on red blood cell (RBC) volume. Dense, dehydrated RBC (DRBC) are observed in SCD patients, and their number correlates with hemolytic parameters and complications such as renal dysfunction, leg ulcers and priapism. To identify new genes involved in RBC hydration in SCD, we performed the first genome-wide association study for DRBC in 374 sickle cell anemia (HbSS) patients. We did not find genome-wide significant results, indicating that variants that modulate DRBC have modest-to-weak effects. A secondary analysis demonstrated a nominal association (P=0.003) between DRBC in SCD patients and a variant associated with mean corpuscular hemoglobin concentration (MCHC) in non-anemic individuals. This intronic variant controls the expression of ATP2B4, the main calcium pump in erythrocytes. Our study highlights ATP2B4 as a promising target for modulation of RBC hydration in SCD patients.