PubMed Health⌕ Search

Biomedical subjects

A G Kendall

Publications and source records attributed to A G Kendall.

At least 19 recordsLinked to original sources
PubMed1992

Two novel beta-thalassemia mutations in the 5' and 3' noncoding regions of the beta-globin gene.

Two novel beta-thalassemia mutations are described. The first mutation, found in an Italian family, is a G----A substitution in nucleotide (nt) +22 relative to the beta-globin gene Cap site. This mutation creates a cryptic ATG initiation codon, the utilization of which for translation would result in premature termination 36 bp 3' downstream. The second mutation, found in an Irish family, is a T----C substitution in nt +1570, or 12 bp 5' upstream of the AATAAA polyadenylation signal in the 3' noncoding region. It is postulated that this mutation leads to destabilization of the encoded beta-globin mRNA.

Adult↗
PubMed1986

Molecular characterization of an atypical beta-thalassemia caused by a large deletion in the 5' beta-globin gene region.

We describe a Canadian family of Czechoslovakian descent that came to our attention because of an HbA2 percentage approximately twice that of an average case of heterozygous beta-thalassemia. This unique phenotype suggested to us the possibility of a novel genetic mechanism being responsible for their beta-thalassemia. To investigate this possibility, we mapped, cloned, and sequenced the mutant beta-globin allele. This molecular analysis demonstrated the presence of a unique 4,237 base pair (bp) deletion extending from 3.3 kilobases (kb) 5' of the beta-globin mRNA cap site to approximately the middle of beta IVS-2. This truncated beta-globin gene further extends the heterogeneity of mutations known to cause beta-thalassemia and delineates new sequences involved in nonhomologous recombination events in the beta-globin gene region.

Aged↗
PubMed1981

Hemoglobin A2 in hyperthyroidism.

Erythrocyte hemoglobin A2 (Hb A2) was quantitated in 28 hyperthyroid patients prior to antithyroid therapy and at intervals during therapy. Fetal hemoglobin (Hb F) levels and red cell mean corpuscular volume (MCV) were also monitored. Before therapy, Hb A2 was significantly elevated (mean +/- SD, 3.3 +/- 0.5%: normals, 2.5 +/- 0.3%: p less than 0.001). Hb F levels exceeded 1.0% in 10 cases. A tendency to red cell microcytosis was also observed (mean MCV 81.1 fl). To-date 10 of these subjects have had adequate studies following appropriate and sustained responses to antithyroid therapy. All showed a fall in Hb A2, usually accompanied by a rise in red cell MCV. A hematologic profile for hyperthyroidism is proposed.

Erythrocyte Volume↗
PubMed1980

Inherited variants of human red cell carbonic anhydrases.

The present state of knowledge concerning the genetic control of human red cell carbonic anhydrases I and II (CA I and CA II) is reviewed. A total of 25 electrophoretic variants, and one deficiency variant of CA I, and 7 electrophoretic variants of CA II have been discovered after screening a minimum of about 50,000 (CA I) and 39,000 (CA II) individual bloods from a variety of human populations. The amino acid substitution has been determined for 8 of the CA I variants and one of the CA II variants. Three previously undescribed variants of CA I (CA I Montreal-1, CA I Montreal-2, and CA I Montreal-3) and two new variants of CA II (CA II London and CA II Detroit) are reported. Three of the CA I variants (CA I Australia-1, CA I Bombay, and CA I Mindanao), and four of the CA II variants (CA II2, CA II Australia, CA II Bombay, and CA II Baniwa) were observed to occur at frequencies of greater than 1%; however, CA I Bombay, CA I Mindanao, CA II Bombay, and CA II Baniwa appear to be private polymorphisms limited to small populations. None of the electrophoretic variants, or the CA I deficiency variant, even in the homozygous state, appear to be associated with any clinical disorder. A defective form of CA I reported as possibly responsible for an inherited type of renal tubular acidosis has not been characterized sufficiently to exclude the possibility of secondary effects.

Amino Acid Sequence↗
PubMed1977

Erythrocyte carbonic anhydrase I: inherited deficiency in humans.

The virtually complete absence of erythrocyte carbonic anhydrase I is reported in three members of a family from the Greek island of Icaria. Two members with moderately reduced levels are believed to be heterozygous for the deficiency. There are no obvious hematological or renal consequences of the severe deficiency state.

Carbonic Anhydrases↗
PubMed1977

Red cell pyruvate kinase deficiency: adverse effect of oral contraceptives.

Erythrocyte enzymopathies are being detected with increasing frequency. The homozygous state for pyruvate kinase (PK) deficiency usually causes chronic non-spherocytic haemolytic anaemia. Aggravation of the condition by a variety of extrinsic factors has been reported, but drugs have rarely been incriminated. A case of severe PK deficiency is presented in which an anovulant drug upsets the usual haematologic balance. This strengthens the suspicion that contraceptive pills may be hazardous in such patients.

Adult↗