Differences in the prevalence of a TaqI RFLP in the 3' flanking region of the α1-proteinase inhibitor gene between asthmatic and non-asthmatic black and white South Africans

The prevalence of the Taq I(‐) allele in variants of α1‐proteinase inhibitor (α1PI) was investigated in a group of 28 black asthmatic patients and 32 black control individuals, and was compared to 43 white asthmatic patients and 32 white control individuals. The plasma concentration of α1PI was determined in eight black and 14 white asthmatics without the Taq I(‐) allele, and compared to seven black and three white asthmatics with the Taq I(‐) allele. Alpha‐1‐PI concentration was also determined in 10 black and 29 white control individuals without the Taq I(‐) allele and compared to seven black and three white controls with the Taq I(‐) allele. There was a highly significant difference in the frequency of the Taq I(‐) allele between black South Africans (24.1%) and white South Africans (6%) (p