Immunogenetic systems of the mink: problems of evolution
Baranov, O.K.
Genetika 23(6): 1026-1037
1987
ISSN/ISBN: 0016-6758 PMID: 3623092 Document Number: 289259
The main features of the organization of the genetic systems of mink sera allotypes (the Ld system of low density lipoproteins, the multigene families of the Lpm-proteins, .gamma.-immunoglobulin heavy and light chains) are described. The species-specific genes for these systems were identified. The mink differs from the other mustelidae representatives in these systems. The saltatory transformation in phylogenesis of the mink Lpm and C.gamma. gene families is emphasized. Hypotheses explaining the appearance of 9 new mink Lpm genes, contributing mainly to the allotypic polymorphism of the Lpm system, are briefly outlined. Possible causes for unusually high frequency of unstable quantitative phenotypic expression of C.gamma.-genes in adult minks, and the evolutionary-genetic mechanisms of the saltatory evolution of this multigene family are discussed. Rapid appearance, during phylogenesis of mink under domestication, the great genetic variability and instability, similar to the mutations of homeotic genes or transposition booms, may be largely the result of activation of silent genes and may be induced by destabilizing selection, according to D. K. Belyaev. Taken together, the results are in agreement with the ideology of punctualism, claiming that macromutations play the main role in speciation. These macromutations produce saltatory transformations in the multigene families.