AAT Variants Research Articles

Genetic diversity of the alpha-1-antitrypsin gene in Africans identified using a novel genotyping assay.

The highly polymorphic human alpha-1-antitrypsin (AAT) gene, more recently named SERPINA1, codes for the most abundant circulating plasma serine protease inhibitor, protease inhibitor 1 (PI). Most studies determining AAT haplotype frequencies have been restricted first by the limited accuracy of the phenotypic method used and secondly by the analysis of predominantly Caucasian populations. Limited studies have been performed on African-based populations. Here a new comprehensive assay for genotyping the entire coding region, including splice junctions, of the AAT gene was designed. This assay, based on denaturing gradient gel electrophoresis (DGGE), allows for the complete analysis of a single individual in two lanes on a gel. Application of the assay resulted in the identification of nine known AAT variants as well as 13 novel sequence variants, five of which are single nucleotide polymorphisms (SNPs), occurring exclusively in the African-based populations. This is the first comprehensive analysis of the genetic diversity of the AAT gene in a cohort from sub-Saharan Africa.

Alpha 1-antitrypsin genetic phenotypes in a group of children suffering from pulmonary diseases.

Alpha 1-antitrypsin (AAT), the main protease inhibitor of human sera, was studied in a group of 88 children suffering from different pulmonary diseases, with the hope that some of the potential victims of chronic obstructive lung diseases can be identified in time. AAT genetic phenotypes were determined using acid agarose gel electrophoresis, followed by crossed antigen-antibody electrophoresis in agarose gel. Identification of the banding patterns revealed 10.2% of AAT variants. 4.54% of the patients were MZ, 3.40% were MS and 89.77% were MM. During this study, 1 FF and 1 MV subject were also found. All AAT variants were in the group of younger children, under 6 years of age.