Phénotypes de l’alpha-1-antitrypsine dans la population togolaise : mise en évidence d’une fréquence élevée de l’allèle rare Pi dans une ethnie isolat

Objectives

The study, which is a ethnobiologic characterization, investigated α₁-antitrypsin gene polymorphism in the togolese ethnic groups. We aimed to determine the existence of rare or deficient alleles predisposing to pulmonary or hepatic genetic diseases.

Patients and methods

We focused our study on healthy subjects of two samples by comparing 205 Adélé from relative isolated ethnic group alive in mountain region and 255 subjects from pluriethnic population living on Atlantic coastal region. Data analysis was performed by α₁-antitrypsin level quantification and serum isoelectric focusing.

Results

The two alleles Pi^M et Pi^F frequencies are respectively 0.834 and 0.166 in Adélé; 0.989 and 0.011 in the subjects from pluriethnic population. Phenotypes MM and FM distribution in the two groups is significantly different (p < 0.001). However, α₁-antitrypsin polymorphism does not significantly influence proteinic and lipidic profiles of the subjects in the two samples.

Conclusion

The Pi^F allele of α₁ antitrypsin is rare allele in the world global populations. Its very high frequency in Adélé explained by preferential endogamic marriage in this ethnic group. Compared to the subjects from pluriethnic population, more than 30 Adélé subjects present a higher risk to develop pulmonary diseases according to isoform F properties.