Genetic polymorphism of basic proteins from parotid saliva.
Science (New York, N.Y.)
|May 12, 1972
Summary
Genetic analysis of parotid salivas revealed distinct phenotypes in Black individuals, controlled by two codominant alleles. Gene frequencies for parotid basic protein (Pb) differed significantly between Black and Caucasian populations.
Area of Science:
- Biochemistry
- Human Genetics
- Population Genetics
Background:
- Parotid saliva contains proteins that can be genetically determined.
- Electrophoretic methods allow for the study of protein variations.
Purpose of the Study:
- To investigate the genetic basis of parotid saliva protein phenotypes in Black and Caucasian populations.
- To determine the inheritance patterns and gene frequencies of parotid basic protein (Pb).
Main Methods:
- Acid-urea starch-gel electrophoresis was used to analyze parotid saliva samples.
- Phenotypes were observed in 90 Black and 101 Caucasian individuals.
Main Results:
- Three distinct phenotypes were identified in Black individuals, controlled by two codominant autosomal alleles.
- Gene frequencies in Black individuals were Pb(1) = 0.84 and Pb(2) = 0.16.
- One Caucasian individual exhibited a heterozygous phenotype similar to Black individuals, with gene frequencies Pb(1) ~ 0.995 and Pb(2) ~ 0.005.
Conclusions:
- Parotid basic protein (Pb) exhibits a genetic polymorphism.
- Significant differences in Pb gene frequencies exist between Black and Caucasian populations.
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