Glutamate Pyruvate Transaminase Null Allele (GPT°) in the Navajo

Abstract

During genetic linkage studies of retinitis pigmentosa in a Navajo Amerindian family, an apparent null allele of erythrocyte GPT (GPT⁰) was observed in a man and 2 of his daughters. This is the fourth description of a (GPT⁰) allele, the first outside of Europe and the first in the Navajo.

Weaving the Strands of Life (<em>Iiná Bitł'ool</em>): History of Genetic Research Involving Navajo People

“…A distinct blood disorder, methemoglobinemia, relates to an overproduction of methemoglobin in erythrocytes, was described in three related Navajo individuals (Balsamo, Hardy, & Scott, 1964). Another study identified a null (silent) allele in glutamate pyruvate transaminase (GPT) in three members of a Navajo family (Crist et al, 1985). In summary, blood/HLA typing, proteins and enzymes in Navajo people were used to make inferences about population similarity, disease associations, and how distinct they were from other Indigenous populations.…”