title: Analysis of crossover type in the alpha -3.7 haplotype among sickle cell anemia patients from various parts of Africa.
abstract: The frequency of alpha+-thalassemia has been determined in African populations carrying beta S-chromosomes of different origins. All these alpha+ thalassemias result from a right-ward deletion. Restriction mapping of the alpha -3.7/haplotype with the enzyme ApaI only showed the presence of a type I crossover. RsaI polymorphism at the 5' end of Z alpha 2 is largely represented in the normal population (gene frequency 23%) but, in our series, never associated with the alpha -3.7/haplotype.
mesh_terms: D000349:Africa; D000755:Anemia, Sickle Cell / Q000150:complications / Q000235:genetics*; D002872:Chromosome Deletion; D003434:Crossing Over, Genetic; D005787:Gene Frequency; D006239:Haplotypes; D006801:Humans; D012150:Polymorphism, Restriction Fragment Length; D013789:Thalassemia / Q000150:complications / Q000235:genetics*