Ruth N. Wrightstone

Quantitation of hemoglobin α chains in adult and fetal goats; gene duplication and the production of polypeptide chains

Abstract The relative amounts of three hemoglobin α chains, the I α , II α , and I α B chains have been determined in normal adult, fetal and newborn goats, in goats with a heterozygosity for the Hb β D or the Hb I α B allele, and in goats with a homozygosity for the Hb I α B allele. Several animals were studied when the β A (and β D ) chains were in part or almost completely replaced by the β C chain, which is the product of a dormant gene. The data indicate: 1. 1. An increase in the relative and absolute amounts of II α chains in adult and newborn goats in the presence of the Hb I α B allele; this increase was about 15% for the adult heterozygous AB goat, and about 32% for the adult homozygous BB goat. 2. 2. The relative amounts of the three α chains are not altered when the β A production is (partially) replaced by that of the β D or β C chains. 3. 3. The percentages of I α B chains in the newborn AB and BB goats are significantly higher than those observed in the corresponding adult goats; this increase is accompanied by a corresponding decrease in the percentages of the II α chain and probably not of the I α chain. The observed changes were found to be more or less directly related to the amount of fetal hemoglobin present in the blood samples. These observations have been interpreted to mean that a certain selective preference of non-α polypeptide chains for specific α polypeptide chains to form dimer subunits may be of importance for the control of the rate of synthesis of hemoglobin molecules in addition to control mechanisms at the gene or ribosome level.

Hemoglobin Louisville (β42 (CD1) Phe→Leu): an unstable variant causing mild hemolytic anemia

An unstable hemoglobin variant termed Hb Louisville, was found in four members of a Caucasian family, who were suffering from a mild hemolytic anemia. The variant showed a decreased stability upon warming at 65 degrees C and an increased tendency to dissociate in the presence of sulfhydryl group-blocking agents. The structural abnormality was identified as a replacement of phenylalanyl residue in position 42 (CD1) by a leucyl residue. Substitution of this phenylalanyl residue, which participates in the contact with heme, by a nonpolar leucyl residue has apparently less severe consequences than a replacement of the same residue by a polar seryl residue as in Hb Hammersmith. Oxygen equilibrium studies of total hemolysate from one Hb Louisville heterozygote indicated a decreased oxygen affinity, a marked decrease in heme-heme interaction, and a normal Bohr effect. Studies with isolated Hb Louisville were not made because it was not possible to separate the variant from normal Hb A.

The structure of goat hemoglobins: IV. A third β chain variant (βE) with three apparent amino acid substitutions

Abstract The presence of a third type of hemoglobin β chain, termed βE, in nonanemic domestic goats is reported. Structural analyses showed that this β chain differs from the βA chain at a minimum in three amino acid residues, namely, the replacement of a Glx (likely glutaminyl) residue by a histidyl residue in peptide T-10, a lysyl residue by an arginyl residue in peptide T-11, and a leucyl residue by a valyl residue in peptide T-13. All available evidence indicates that the structural gene producing the βE chain is allelic to the gene producing the βA chain. Thus, the variance in the structure of goat hemoglobin βE chain is likely the result of an allele with multiple replacements at a single Hbβ structural locus.

Hemoglobin atlanta or α2β275 Leu→Pro (E19); An unstable variant found in several members of a caucasian family

Abstract Hemoglobin Atlanta, α 2 β 2 75 Leu→Pro (E19) , has been found in several members of three generations of a Caucasian family living in metropolitan Atlanta. The abnormal hemoglobin is one of the nine unstable variants in which either a leucyl or an alanyl residue is replaced by a prolyl residue. These substitutions have been observed in the B, E, F, and G helixes of the β chain and in the H helix of the α-chain. Hemoglobin Atlanta heterozygotes are mildly affected by the presence of this unstable hemoglobin.

Hemoglobinopathies observed in the population of the Southeastern United States (SE-USA).

A survey of nearly 250,000 citizens of Georgia and South Carolina conducted during the past twenty years has led to the detection of over 40 abnormal hemoglobins and several additional hemoglobinopathies. The presence of some of these hemoglobin abnormalities cause (severe) clinical symptoms but others remain undetected unless a specific search is initiated. The incidence of Hb S varies slightly among the populations of different areas, and appears to be the highest in the coastal counties of Georgia and South Carolina. A survey of over 17,000 persons of mainly high school and college age has shown that a significant number of cases with clinically significant hemoglobinopathies will remain undetected unless such surveys are actively promoted.

Hb-Genova (α2β228(bio)leu→pro); methods for detection and analysis of unstable hemoglobins

Abstract The third occurrence of the unstable β chain variant Hb-Genova is described. The variant is characterized by replacement of a leucyl residue in position 28(B 10) by a prolyl residue. The abnormality was discovered in a Canadian woman of Ukrainian ancestry, who had a persistent anemia with Heinz bodies prevalent since early childhood. The techniques used in the detection of unstable hemoglobins are reviewed.

Hb Camden and Hb Hope Found During Routine Testing

The electrophoretically fast-moving hemoglobin variant Hb Camden [beta131 (H9) gln leads to glu] has been found in a middle-aged female suffering from pulmonary disease, and Hb Hope [beta136 (H14) gly leads to asp] which migrates just ahead and very close to Hb A was present in a young obstetrical patient with a mild hemolytic anemia.

Studies on the heterogeneity of hemoglobin : XVI. Separation of variants with a Glu→Lys substitution by chromatography on CM-cellulose

Abstract Six β chain variants, two α chain variants, and one δ chain variant each with a substitution of a glutamyl residue for a lysyl residue in different positions, and Hb-C-Harlem, Hb-A2, and Hb-Miyada have been analyzed by CM-cellulose chromatography. These variants can be divided into two groups as follows: Group I C, C-Siriraj, A2-Melbourne, Agenogi, O-Arab, O-Indonesia, and C-Harlem; Group II Hb-E-Saskatoon, Hb-Chad, Hb-E, Hb-A2, and Hb-Miyada. The variants of group I are eluted at an elution pH value which differs 0.3–0.43 pH units from that of Hb-A, whereas this difference for the variants of Group II is only 0.2 pH units. These observations have been discussed in the light of our present knowledge of the structure of the hemoglobin molecule. The difference between the elution pH values of many variants and that of Hb-A2 makes it possible to use this technique for the quantitation of Hb-A2 in red cell hemolysates containing hemoglobins which have electrophoretic mobilities similar to that of Hb-A2.

Some physicochemical properties of hemoglobin-manitoba (α2102Ser → Arg(G9)β2)

Hb-Manitoba was discovered in 1970 [1] in a Canadian family of British origin. Recently we observed the same variant in a second family, and found that the oxy-derivative of Hb-Manitoba is slightly unstable at 65 degrees C, dissociates less readily at alkaline pH than does Hb-A, and forms asymmetric hybrids with other hemoglobins which are readily detectable by electrophoresis.

Hb Etobicoke, α85(F5) Ser → Arg Found in a Newborn of French-Indian-English Descent

During a recent testing program for hemoglobin (Hb) abnormalities in cord bloods of newborns in the State of Georgian an α-chain variant was discovered in a male Caucasian infant of French-Cherokee Indian-English descent. The hematological values of the infant at five weeks were: Hb 8.9 g/dl, RBC 2.99 × 1012/1; PCV 0.28 1/1, MCV 93 fl, MCH 30.4 pg, and MCHC 31.2%. Corresponding results on both parents were normal. Although the abnormal Hb was not found in either parent, paternity studies were not done. The variant had a mobility of Hb G on cellulose acetate electrophoresis at PH 8.6 and could not be detected by citrate agar electrophoresis at pH 6.1 (1). DEAE-cellulose chromatography with glycine-KCN-NaCl developers (2) redily separated the abnormal Hbs from Hb A, Hb F, and Hb F1 partially separated Hb Fx from Hb X. The combined concentration of the Hb Fx was 16% in the cord blood red cell lysate. A repeat chromatogram at five weeks of age showed improved separation and gave the concentration of Hb Fx as ...