title: Association between sickle cell anemia and alpha thalassemia reveals a high prevalence of the α3.7triplication in congolese patients than in worldwide series.
abstract: BACKGROUND
  Information about the association with alpha thalassemia in sickle cell patients is unknown in the Democratic Republic of Congo. There is very little data on the alpha thalassemia in patients suffering from sickle cell anemia in Central Africa, and their consequences on the clinical expression of the disease.
  
  
  METHODS
  A cross-sectional study was conducted in 106 sickle cell patients living in the country's capital Kinshasa. The diagnosis of sickle cell anemia was confirmed with a molecular test using PCR-RFLP (restriction fragment length polymorphism) technique. The diagnosis of thalassemia was performed by the technique of multiplex ligation dependent probe amplification.
  
  
  RESULTS
  The mean age of our patients was 22.4±13.6 years. The α3.7heterozygous deletion, the α3.7homozygous deletion and the α3.7triplication were respectively encountered in 23.6%, 25.5% , and 11.3% of patients. Patients with normal αα/αα genotype represented 39.6% of the study population. The average of severe vaso-occlusive crises, the rates of blood transfusions per year, the rate of osteonecrosis, cholelithiasis and leg ulcers were significantly lower in the group of patients with α3.7homozygous deletion and α3.7triplication.
  
  
  CONCLUSIONS
  The prevalence of α3.7triplication was higher in sickle cell patients in the Democratic Republic of Congo than in worldwide series. The α3.7triplication and α3.7homozygous deletion were associated with less severe forms of the Sickle cell anemia in Congolese patients. These results showed the need to investigate systematically the alpha-globin gene mutations in sickle cell population in Central Africa.
authors.affiliation: Center for Human Genetics, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.|Department des Sciences de Bases, Laboratory of Biochemistry and Molecular Biology, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.|Sickle Cell Center of Yolo, Kinshasa, Democratic Republic of Congo.
authors.forename: Tite Minga
authors.initials: TM
authors.lastname: Mikobi
authors.affiliation: Center for Human Genetics, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.|Center for Human Genetics, Katholieke Universiteit te Leuven, Leuven, Belgium.|Department of Pediatrics, University Hospital of Kinshasa, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.|Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo.
authors.forename: Prosper Tshilobo
authors.initials: PT
authors.lastname: Lukusa
authors.affiliation: Division of Hemato-oncology and Nephrology, Department of Pediatrics, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.
authors.forename: Michel Ntetani
authors.identifier: http://orcid.org/0000-0002-7479-1170
authors.initials: MN
authors.lastname: Aloni
authors.affiliation: Center for Human Genetics, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.|Center for Human Genetics, Katholieke Universiteit te Leuven, Leuven, Belgium.|Department of Pediatrics, University Hospital of Kinshasa, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.|Institut National de Recherche Biomédicale, Kinshasa, Democratic Republic of Congo.
authors.forename: Aimé
authors.initials: A
authors.lastname: Lumaka
authors.affiliation: Division of Biostatistics and Epidemiology, School of Public Health, University of Kinshasa, Kinshasa, Democratic Republic of Congo.
authors.forename: Pierre Zalagile
authors.initials: PZ
authors.lastname: Akilimali
authors.affiliation: Center for Human Genetics, Katholieke Universiteit te Leuven, Leuven, Belgium.
authors.forename: Koenraad
authors.initials: K
authors.lastname: Devriendt
authors.affiliation: Center for Human Genetics, Katholieke Universiteit te Leuven, Leuven, Belgium.
authors.forename: Gert
authors.initials: G
authors.lastname: Matthijs
authors.affiliation: Division of Hemato-Immuno-Rheumatology, Department of Internal Medicine, Faculty of Medicine, University of Kinshasa, Kinshasa, Democratic Republic of Congo.
authors.forename: Jean-Marie
authors.initials: JM
authors.lastname: Mbuyi Muamba
authors.affiliation: Center for Human Genetics, Katholieke Universiteit te Leuven, Leuven, Belgium.
authors.forename: Valerie
authors.initials: V
authors.lastname: Race
mesh_terms: D000293:Adolescent; D000328:Adult; D000755:Anemia, Sickle Cell / Q000150:complications / Q000453:epidemiology / Q000235:genetics; D002648:Child; D003430:Cross-Sectional Studies; D015023:Democratic Republic of the Congo / Q000453:epidemiology; D005260:Female; D020440:Gene Duplication / Q000235:genetics; D006801:Humans; D008297:Male; D015995:Prevalence; D055815:Young Adult; D017085:alpha-Thalassemia / Q000150:complications / Q000453:epidemiology / Q000235:genetics
keywords: Kinshasa; alpha thalassemia; multiplex ligation dependent probe amplification; sickle cell anemia; the Democratic Republic of Congo, Africa; α3.7 triplication