Prevalence of the sickle cell trait among students in a physical education college in Côte-d'Ivoire.

The prevalence of sickle cell trait (SCT), was studied in 263 students enrolled in a physical education college in Côte-d'Ivoire. Most of the students were athletes of average training level, but some competed at an international level. The prevalence of SCT (hemoglobin AS), observed in the student population (13.7%) was not significantly different from that of the general population (12%) of Côte-d'Ivoire and did not differ between sexes. The percentage of international level athletes was similar in SCT (25%) and control (hemoglobin AA) groups (25.7%). Particular activities practised by SCT international level athletes were individual track events (sprint race, 400 m race and long and high jump) as well as team sports (football and handball), indicating the excellent aptitude for aerobic and anaerobic metabolic activities. As none of the international athletes engaged in endurance activities, no conclusions can be drawn regarding either the aptitude of SCT subjects for intense and prolonged exertion or a possible limitation of oxygen transport produced by their hemoglobinopathy.

[Hereditary elliptocytosis in the Ivory Coast]. / Contribution à l'étude de l'elliptocytose héréditaire en Côte d'Ivoire.

The authors report 6 cases of hereditary elliptocytosis during a screening in one thousand (1,000) black persons. The analysis of these cases of elliptocytosis allow to draw the following conclusions: the frequency of the hereditary elliptocytosis varies between 0.6 to 1 per cent in Ivory Coast, the functional and structural analysis of spectrin show a high global frequency of the elliptocytosis of Model I in relation with an abnormally of alpha I domain of spectrin, all the cases detected don't give any clinical trouble.

[A case of association of Hb C Ziguinchor (alpha A2 beta 6-2 (A3) Glu replaced by Val beta 58 (E2) Pro replaced by Arg) with a hereditary persistence of fetal hemoglobin (HPFH). Clinical and biological results]. / Un cas d'association d'Hb C Ziguinchor (alpha A2 beta 62 (A3) Glu----Val beta 58 (E2) Pro----Arg) avec une persistance hereditaire d'Hb foetale (PHHF).

The authors report on one case of association between Hb C Ziguinchor and an hereditary persistence of Hb foetal. Despite an high rate of Hb F estimated at 37,2% painful manifestations due to Hb S (beta 6 Glu-Val) mutation are present.

[Hematologic profile of hemoglobin "Hope" (beta 136 (H14) Gly-Asp) in the West African]. / Profil hématologique de l'hémoglobine "Hope" (beta 136 (H14) Gly-Asp) dans l'ouest Africain.

Detection of 11 cases of hemoglobin "Hope" after family study in three isolated cases led us to establish an hematologic profile of this hemoglobin. The first observation which can be done is the geographic origin of the propositus. All of these originated from the sub-sahelian zone. The second observation is the discovery of anemia for all carriers of this hemoglobin.

Cardiorespiratory adjustments in chronic sickle cell anemia.

During the intercrisis periods, patients homozygous for sickle cell anemia (SS) show clinical symptoms of severe impairment of oxygen transport mechanisms. We have determined respiratory lung function tests, arterial and venous blood gases and cardiocirculatory parameters in 39 SS patients (mean age 22 +/- 5 yr) at distance from any vaso-occlusive crisis or blood transfusion. The patient group was compared to subjects homozygous for HbA (AA) of the same ethnic origin. Determinations were made at rest and after a 5 min mild exercise period. The main alterations in oxygen transport parameters observed in SS patients were: 1) a moderate reduction in vital capacity and maximal ventilation (pure restrictive syndrome), 2) an arterial hypoxemia which worsened the already low oxygen content of blood due to anemia, and 3) a low arterio-venous oxygen saturation difference which is very surprising in anemic patients. The normal oxygen consumption rate was thus insured by a 70% increase of the cardiac output at rest. A particular abnormality found in SS patients was the high Po2 in mixed venous blood. The decreased affinity of blood for oxygen resulting from the polymerization of HbS in the erythrocytes led to an almost normal venous blood unsaturation and thus a decreased release of oxygen from this anemic blood. These results indicate that peripheral blood flow was permanently increased in SS patients. This may be in part at the origin of the arterial hypoxemia induced by an increased pulmonary blood shunting. Sickle cell anemia is more severe than other anemias of comparable intensity as, due to the sickling process, these patients appear to be at the upper limit of physiological compensatory mechanisms usually encountered in chronic anemia.

[Rare hemoglobins in Ivory Coast and West Africa]. / Les hémoglobines rares en Côte d'Ivoire et en Afrique occidentale.

Detection of drepanocytosis, which affects 12 p. 100 of the people living in Ivory Coast, is a part of the routine check up performed in hospitals. In 13 years of screening, electrophoresis has been carried out on about 170,000 samples. This work has led the authors to the typing of a certain number of uncommon hemoglobins (277 cases). As the technical methods have been greatly improved over the past few years, it is most likely that new hemoglobin mutants will continue to be discovered. A special interest of their typing consists in the fact these hemoglobins seem to be found either within specific areas or in special ethnic groups.

Sickle gene. Its origin and diffusion from West Africa.

Linked DNA polymorphisms can be used to study the evolution of structural gene mutations. Both the beta S-(beta 6Glu leads to Val) and beta C-(beta 6Glu leads to Lys) genes are common in West Africa. We have analyzed their linkage to a polymorphic Hpa 1 site appearing 3' to the beta-globin gene locus in selected populations from Wes Africa. A large reservoir of beta A-genes linked to 13-kilobase Hpa 1 fragments with a frequency of 17-18% has been identified. In addition, the beta S- and beta C-genes in Togo are found to be tightly linked to the 13-kilobase Hpa 1 fragment, whereas 72% of the beta S-genes in the Ivory Coast reside on the 7.6-kilobase Hpa 1 fragment. These studies are consistent with the selection and expansion of two different chromosomes bearing beta S-genes in at least two physically close, but ethnically separate regions of West Africa, with subsequent diffusion to North, Equatorial, and East Africa.

[Polymorphism of hemoglobins D in Ivory Coast: Hb Korle Bu (beta 73 (E17) Asp leads to Asn), Hb Avicenna (beta 47 (CD6) Asp leads to Ala) and Hb Cocody (beta 21 (B3) Asp leads to Asn) (author's transl)]. / Polymorphisme des hémoglobines D en Côte-d'Ivoire : hémoglobine Korle Bu (bêta 73 (E17) Asp leads to Asn), hémoglobine Avicenna (bêta 47 (CD6) Asp leads to Ala) et hémoglobine Cocody (bêta 21 (B3) Asp leads to Asn).

A recent screening performed at the CHU Cocody in Abidjan (Ivory Coast) revealed six cases of hemoglobin "D". The use of a rapid strategy based on isoelectric focusing studies, finger-printing, reverse phase high performance liquid chromatography and solid phase microsequence technique led to the characterization of three abdominal hemoglobins. The first variant corresponded to the Hb Korle Bu (beta 73 (E17) Asp leads to Asn) (pI = 7.210) which is common in this country. The second, Hb Avicenna (beta 47 (CD6) Asp leads to Ala) (pI = 7.225) has not yet been reported in Africa. The last one was a new variant, Hb Cocody (beta 21 (B3) Asp leads to Asn) (pI = 7.205). A large number of hemoglobin "D" have been detected in European, American negroes, Amerindian or Asiatic populations, but only few observations were reported in Africa. Large screenings and discriminative methodologists must provide information on the polymorphism of hemoglobin D in the African population.

Haemoglobin K Woolwich: a study of the family of a homozygote.

A family is described in which the proband is homozygous and several relatives are heterozygous for Hb K Woolwich (beta 130 [H10] Lys leads to Gln). These people are clinically and haematologically normal. The relationship between the presence of Hb K Woolwich and beta +-thalassaemia is discussed. The distribution of Hb K Woolwich in West Africa is discussed and it is seen to be closely associated with the Akan group.

Polymorphism of erythrocyte and serum enzyme systems in the Gagu of the Ivory Coast.

Erythrocyte and serum enzyme system in the Gagu of the Ivory Coast have been investigated. Some systems (e.g. PGM) differ little between the subdivisions of the Gagu group, but others differ considerably (e.g. G6PD variants). In general the red cell enzyme frequencies fall within the range of variation characteristic of African populations. Serum cholinesterase variants are present only at low frequency, and the distribution of alkaline phosphatase phenotype shows the expected correlation with ABO blood groups.