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T F Thurmon

Publications and source records attributed to T F Thurmon.

48 records · Page 3Linked to original sources

Silent hemoglobin alpha genes in apes: potential source of thalassemia.

Small quantities of unusual hemoglobins were found in 1 of 37 chimpanzees and 2 of 6 gorillas. In each genus these hemoglobins contain unique alpha chains that differ from the ordinary by eight to nine scattered amino acid changes. The unusual chains arise from a hitherto undetected hemoglobin (3)alpha locus. No (3)alpha products are found in most apes; accordingly, (3)alpha is considered synthetically inactive in all but a few reversion mutants. Indirect evidence that the inactive (3)alpha locus is juxtaposed to an active alpha locus together with the supposition that (3)alpha exists in man provides a setting wherein thalassemia might be produced by nonhomologous recombination between two loci.

Amino Acid Sequence↗

Hemoglobins A and A2 in New World primates: comparative variation and its evolutionary implications.

Hemoglobin A(2) (alpha(2)delta(2)) in New World primates represents about 1/160 to 1/16 of total hemoglobin and, by virtue of this low proportion, is presumed to be functionally unimportant. Nonetheless, A(2) exhibits genetic polymorphism by electrophoresis in three out of five genera, whereas the major component, hemoglobin A (alpha(2)beta(2)), is electrophoretically invariant. Moreover, in four genera, including man, the evolutionary accumulation of mutations has been greater in delta than in beta Such findings suggest that both polymorphism and evolutionary changes can accrue to an effectively functionless and thus selectively nearly netutral gene.

Amino Acid Sequence↗

Genetic considerations in human cancer incidence.

Analysis by the methods of genetic demography can offer plausible explanations for the unusual distribution of cancer in an area of high incidence. The important demographic characteristics include inbreeding, founder effect, and racial admixture. Inbreeding would elevate cancer incidence if autosomal recessive genes played a role in cancer etiology. Founder effect would limit this phenomenon to those recessive genes observed in the founding group and result in a cancer spectrum different from that of the surrounding populations. The preference of a racially admixed group for classification as white could result in an excess of cancer patients being classified as white. The population groups in southern Louisiana typify the kind of "human genetics laboratory" that inbred groups offer to investigators of the genetic aspects of cancer.

Adult↗