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Colour-blindness and sensitivity to PTC in Hadza
1Department of Anthropology, University College, London.
Annals of Human Biology
|January 1, 1975
Summary
The Hadza people of Tanzania show high rates of red-green color blindness and phenylthiocarbamide (PTC) taste deficiency. These genetic traits were studied using Ishihara plates and PTC testing solutions.
Area of Science:
- Anthropology
- Human Genetics
- Population Studies
Background:
- The Hadza are a hunter-gatherer population in Tanzania.
- Understanding genetic diversity in isolated populations is crucial for evolutionary studies.
Purpose of the Study:
- To investigate the prevalence of red-green color blindness and phenylthiocarbamide (PTC) taste deficiency in the Hadza population.
- To compare these genetic traits with other African populations.
Main Methods:
- Red-green color blindness was assessed using Ishihara non-numeral plates in 211 Hadza males.
- PTC taste deficiency was evaluated in 118 individuals using a single solution and sorting test, with a follow-up detailed threshold test on 53 eastern Hadza males.
Main Results:
- Three individuals were identified as protanopes, suggesting possible gene flow from an Isanzu ancestor.
- Initial PTC testing revealed 22% of males and 27% of females as non-tasters.
- Further analysis estimated 43% of eastern Hadza males as non-tasters, a high prevalence for an African population.
Conclusions:
- The Hadza exhibit notable frequencies of red-green color blindness and PTC non-tasting.
- These findings contribute to the understanding of genetic variation within African populations and potential evolutionary influences.
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