ISSN:
1432-1203
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary In order to evaluate the polymorphism of hemoglobin in a population of Equatorial Africa, we undertook a prospective study of 146 births at a rural maternity hospital close to Brazzaville (P.R. Congo). This showed among the mothers 31 (22%) carriers of the sickle cell trait (AS), six with δ mutation, and two with β-thalassemia triat. Among the children, 27 (18.5%) had sickle cell trait and one had sickle cell homozygosity. The frequency of the HbF Sardinia trait was 7.5%. This and other studies suggested a dilution gradient from Europe to Africa. Hemoglobin Bart's could be visually detected in 23.3% of the new-born babies. We attempted to distinguish between those infants with a high level of Hb Bart's (Bart's ++ group: 13.7%) and a group with a detectable Hb Bart's level that in our experimental conditions is between 1 and 2% (Bart's + group: 9.6%). Mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) were 88.6 ±5.7 fl and 29.0±2.1 pg in the Bart's ++ group; 94.5±10.9 fl and 30.6±4.1 pg in the Bart's + group; whereas they were 101.0±8.7 fl and 33.9±2.5 pg in the control group. Since iron dificiencies are very rare in new-borns and selecting according to published data on black people as homozygous α-thalassemia of the type I (-α/-α), individuals of the Bart's ++ group whose MCV was below 95 fl and MCV below 30 pg, the gene frequency is estimated to be 34% and that of heterozygotes (-α/αα) 45%. These high frequencies were confirmed in AS mothers: 45% showed a significant decrease of the S fraction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00278785
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