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1

Regional genetic variability among South African vervet monkey Chlorocebus aethiops populations

100%
Grobler P. J., Matlala J. M.
Acta Theriologica
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2002
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tom 47
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nr 2
A South African rehabilitation centre for illegally kept vervet monkeys Chlorocebus aethiops Linnaeus, 1758 required an evaluation of the genetic status of vervet monkeys, to determine whether animals from different geographical areas may be mixed. We studied animals originating from three geographical regions and used biochemical genetic and morphological approaches to address this question. The most prominent trend from allozyme data was derived from the locus Prt-2 (an unspecified serum protein), where each of the three populations could be characterised by the absence or presence of unique alleles. Nevertheless, statistical coefficients indicated little genetic divergence, with genetic distance values of 0.001-0.003 and an overall fixation index value of 0.046. Average heterozygosity did not differ appreciably among populations (2.5-3.3%). The morphological study identified suitable traits, free from the influence of growth allometry, that can be used for inter-population comparisons. No significant morphological differences between con-specific populations were however found. It is concluded that vervet monkeys from the species' wider distribution range is relatively monotypic, but that monkeys from different geographical areas should not be unduly mixed, pending the results of finer grained molecular studies.
2

Genetic characterisation of a domestic dog canis familiaris breed endemic to South African rural areas

80%
Greyling L. M., Grobler P. J., Van Der Bank H. F., Kotze A.
Acta Theriologica
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2004
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tom 49
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nr 3
Allozyme electrophoresis (horizontal starch gel and PAGE) and histochemical staining techniques were used to study the genetic composition of an endemic southern African domestic dogCanis familiaris Linnaeus, 1758, the Africanis breed. Genetic differentiation was analysed at 21 protein-coding loci. The results were compared to those for three other populations/breeds: representatives of established Western breeds, crossbred dogs of Western descent from rural areas in South Africa, and indigenous Saluki dogs from the Middle East. Nine polymorphic loci were found (Ak-1,-2, Ck, Per, Hb, Po-A-1 to-3 andPo-Tf). Two unique alleles at the Ck and Po-A-2 loci separated the Africanis breed from the other groups. There were also significant differences between Africanis and the other breeds in pair-wise comparisons of allelic frequencies at polymorphic loci. An assignment test, fixation index values, gene flow and genetic distance values indicated a closer genetic association between the Africanis and Saluki breeds than with dogs of Western origin. This finding supports archaeological evidence that the endemic Africanis breed was introduced from the Middle East into Africa thousands of years ago, and not through later western influences. The average heterozygosity ranged from 0.106–0.15, with least heterozygosity in the Africanis and most in the rural crossbred group. The percentage of polymorphic loci, the mean number of alleles per locus (biologically more significant than heterozygosity), and conformation of genotypes to Hardy-Weinberg proportions showed no evidence of recent loss of genetic diversity in Africanis. Genetic differentiation and support of archaeological evidence by genetics indicate that the endemic southern African domestic dog breed is unique.
3

Fluctuating asymmetry and allozyme variability in an isolated springbok Antidorcas marsupialis population from the Chelmsford Nature Reserve

80%
Grobler P. J., Taylor P. J., Pretorius M. D., Anderson C. P.
Acta Theriologica
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1999
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tom 44
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nr 2
Allozyme variability and fluctuating asymmetry (FA) in skull morphology were used to test the hypothesis of inbreeding in an isolated springbok Antidorcas marsu­pialis fZimmermann, 1780) population from the Chelmsford Nature Reserve, South Africa. Of 39 loci studied in a sample of 30 animals, five displayed allelic polymorphism. Average heterozygosity of 1.8% was not appreciably lower than a value of 2% calculated for 49 animals from a control group from Beniontein Game Farm in the Northern Cape Province, South Africa. Proportion of polymorphic loci and average number of alleles per locus were identical in both populations (10.3% and 1.1). Morphological analysis contradicted the prediction of increased fluctuating asymmetry due to the likelihood of inbreeding in a small, isolated population, with FA almost always higher in the control compared to Chelmsford. Chelmsford animals were however smaller than control animals for seven out of 9 cranial and horn variables analysed (significantly so in four cases), hich could conceivably be explained by environmental influences. It is concluded that loss of genetic diversity is not a problem in the Chelmsford springbok population, although this does not negate the possibility that physical deformities occurring in the population may indeed be genetically induced.
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