ABSTRACT
A new alpha chain variant Hb Spanish Town, a27 Glutamic acid-Valine, awas detected in the cord blood of a Jamaica Negro infant. In the mother the adult component (a2 Spanish TownB2) has an electrophoretic mobility between haemoglobins S and F at alkaline pH and measures 11.0-12.0 percent of the total haemoglobin. (Summary)
Subject(s)
Humans , Infant, Newborn , Infant , Adult , Female , Hemoglobins, Abnormal , Amino Acid Sequence , Amino Acids/analysis , Blood Protein Electrophoresis , Chymotrypsin , Electrophoresis, Polyacrylamide Gel , Glutamates , Jamaica , Peptide Fragments/analysis , Texas , ValineABSTRACT
15,661 cord bloods from Jamaican infants were examined for abnormal hemoglobins using alkaline cellulose acetate electrophoresis for the initial screening, supplemented by acid agar gel electrophoresis for samples exhibiting abnormal hemoglobin bands. Of the 16 electrophoretic variants which were detected, six were fully characterized and found to be: four Hb F Port Royal (alpha2 Ggamma2 125 Glu replaced by Ala) and two Hb F Victoria Jubilee (alpha2Agamma2 80 Asp replaced by Tyr). The Hb F Port Royal samples each constituted about one eighth of the total Hb F as did seven additional samples presumed to be Hb F Port Royal. The infants with this variant exhibited no special hematological characteristics or other consistent associations. Both Hb F Victoria Jubilee samples ocurred in somewhat lower proportions of the total Hb F compared with Hb F Port Royal and exhibited an apparent increase of free alpha chains in the whole hemolysate. The data available on detectable gamma chain variants suggest that a specific point mutation may occur in either a HbGgamma or a HbAgamma locus. (AU)
Subject(s)
Humans , Infant, Newborn , Male , Female , Fetal Hemoglobin , Hemoglobins, Abnormal , Chromatography, Gel , Electrophoresis, Cellulose Acetate , Hemoglobin A , Genetic Variation , JamaicaABSTRACT
A Gy-chain variant, Hb F Port Royal, with an electrophoretic mobility intermediate between Hb S and Hb C was found in a Jamaican-Negro infant, and made up to 14-15 percent of the total Hb F. A glycinamidation procedure was employed to aid in the determining the amino-acid residu substitution of gamma 123 Glu leads to Ala, and the presence of glycine in position 136. (AU)
Subject(s)
Humans , Infant , Male , Fetal Hemoglobin , Hemoglobins, Abnormal , Amino Acid Sequence , Blood , Chromatography, Gel , Electrophoresis, Starch Gel , Fetal Hemoglobin/isolation & purification , Hemoglobins, Abnormal/isolation & purification , Jamaica , Umbilical CordABSTRACT
Two siblings of mixed Negro, East Indian and Causacian parentage showed an abnormal haemoglobin component in infancy which had electrophoretic characteristics similar to Hb F Roma (Silvestroni & Bianco, 1963). The amino-acid substitution responsible for the peculiar electrophoretic mobility was found to be in the gamma polypeptide chain (gamma-61(E5)Lys-->Glu). The finding of an alanyl residue at position of 136 of the gamma-chain of the abnormal component in the first born of these infants was repeated in the abnormal gamma-chain of the second infant. No functional abnormalities were found to be associated with this abnormal haemoglobin, which is designated Hb F Jamaica (Summary)
