Studies of haemoglobin types in barbary sheep (Ammotragus lervia).

1. Two haemoglobin types, haemoglobins Amm-C and Amm-B, were observed in five Barbary sheep (Ammotragus lervia). One animal was homozygous for haemoglobin Amm-C, a second was homozygous for haemoglobin Amm-B, and three were heterozygous for both. 2. Amino acid analyses of the globin from haemoglobin Amm-B showed that this type was related to, but not identical with, haemoglobin B of the domestic sheep. 3. The beta-chain of haemoglobin Amm-C was found to be composed of 141 amino acid residues. Its amino acid composition differed from that of the beta(C)-chain of the anaemic domestic sheep in at least 14 residues. The Amm-beta(C)-chain contained one isoleucyl residue. 4. The amino acid compositions of tryptic peptides T-1, T-2, T-13 and T-14 of the Amm-beta(C)-chain were similar to those of the sheep beta(C)-chain. Peptides T-3, T-4, T-6, T-7, T-8, T-11 and T-15 were the same as the corresponding peptides of the sheep beta(A)- and beta(C)-chains. Peptide T-5 and to a smaller extent peptide T-9 resembled the corresponding peptides of the sheep beta(A)-chain, and peptide T-10 was identical with peptide gammaT-10 of sheep haemoglobin F. Peptide T-12 was not recovered. 5. The results of these investigations were interpreted as being indicative that the structural Amm-beta(C)-gene is closely related to the beta(C)-gene of sheep, from which through domestication the present domestic sheep originated.