On the one hand, spatial structuring is becoming less marked due to the recombination of founder genotypes at the Aat-1 locus and thus decay of the founder effect
. On the other hand, as establishment of new individuals increases, a new spatial structure emerges due to mating between relatives (6-m-wide patch of clumped individuals of revealed by all loci except Aat-1).
Attempts to examine the stochastic effects of colonization on adaptive traits often encounter problems teasing apart genetic changes resulting from altered selection pressures from those arising from founder effect
and genetic drift (Coyne and Barton 1988; Dennison and Baker 1991; Turner 1992).
The lack of large normal alleles in these groups (alleles within the normal range, but with a larger repeat length) also supports the hypothesis that the expanded alleles are prevalent because of a founder effect
, rather than the independent expansion of large normal alleles.
This theoretical result suggests that models of founder effect
speciation (Mayr 1963; Carson 1968, 1982; Templeton 1980a,b) may not be limited by loss of additive genetic variance due to the founding event and subsequent finite population size.
(20) Researchers at UCT have previously reported founder effects
in the mixed-ancestry population (SCA1 (21) and HD (22)) and the indigenous black African population (SCA7 (23)), with further research ongoing into the HD founder haplotypes.
Speciation via host shifts or founder event should result in significantly lower levels of genetic variation in populations infesting the derived host because of founder effect
It is possible that a founder effect
for HDL2 exists in South Africa, particularly in the northern part of the country, as suggested by Magazi et al.
1015-1016) was that the founder effect
would cause epistatic interactions (in the gene action sense, not the quantitative genetic concept of epistatic variance) to make many gene loci more responsive to selection after the founder effect
(that is, the gene action epistasis is converted into increased additive genetic variance by the founder effect
The genotyping in whites reflects the founder effects
of D154N, D206E and V408M in Afrikaners and del197 in Jews, but these mutations are also present in subjects of mixed ancestry.
The founder effect
in speciation: Drosophila pseudoobscura as a model case.
There was little evidence that island age is associated with differences in genetic variability (other than the founder effect
observed in S.
To do this, we have computed a new measure of distance that corrects for the founder effect
(Chakraborty and Nei 1977).