Molecular and chromosomal polymorphism in continental and insular populations from the southwestern range of Drosophila subobscura

Abstract

Eight insular and continental populations from the south-western range of Drosophila subobscura have been studied with regard to molecular and inversion polymorphisms. Heterogeneity between populations with respect to allele frequencies of 4 gene loci (Amy, Est-8, Est-9 and Pep-I) is the highest known for natural populations of the species. Moreover, the most common allele for these loci is not the same in all populations. Cladograms based on UPGMA clustering of the genetic distances based on allele frequency do not coincide with those constructed with inversion data. The allele-frequency differences between the populations may be due to non-random associations between enzyme alleles and gene arrangements and to founder effects appearing in the insular populations.

Genetic similarity between natural populations of Drosophila ananassae from Kerala and Andaman and Nicobar Islands

“…Genetic identity and distance indexes have been used by many authors to quantify the degree of genetic divergence at the level of chromosomal and allozymic polymorphisms in many species of Drosophila (Powell et al, 1972;Powell, 1973;Ayala et al, 1974 a, b;Prevosti et al, 1975;Fukatami, 1976;Pinsker & Sperlich, 1979;Fontdevila et al, 1981;Singh et al, 1982;Larruga et al, 1983). Ac- cording to Powell (1973) the differences between the populations are higher in chromosomal polymorphism than in allozymic systems.…”

“…The degree of chromosomal variability varies in different species of Drosophila and also in different populations of the same species (Da Cunha, 1960;Dobzhansky, 1970;Sperlich, 1973). The amount of genetic differentiation at the level of chromosomal polymorphism in natural populations of Drosophila has been quantified by using genetic identity and distance (Powell et al, 1972;Prevosti et al, 1975;Fukatami, 1976;Pinsker & Sperlich, 1979;Fontdevila et al, 1981;Larruga et al, 1983).…”

Genetic distance in inversion polymorphism among natural populations of Drosophila ananassae

“…The amount of genetic differentiation has been studied at the level of allozymic and chromosomal polymorphism in many species of Drosophila (Powell et al, 1972;Powell, 1973;Ayala et al, 1974a, b;Prevosti et al, 1975;Fukatami, 1976;Pinsker & Sperlich, 1979;Larruga et al, 1983). The differences between populations are lower in the allozyme systems than in chromosomal polymorphism (Powell, 1973).…”

“…Genetic distance is the genetic difference between populations as expressed by a function of gene frequencies (Nei, 1975). Genetic distance indexes have also been used by many authors to quantify the amount of genetic differentiation at the level of chromosomal polymorphism in natural populations of Drosophila (Powell et aL, 1972;Prevosti et al, 1975;Fukatami, 1976;Pinsker & Sperlich, 1979;Larruga et al, 1983).…”

Blood biochemical polymorphisms as markers for genetic characteristics of wild Spanish and domestic rabbits

“…The statistical methods are in common use (see Larruga et al, 1983). The inbreeding coefficient in the total population, estimated according to the procedure of Kidd et al (1980), will be referred to as f, whereas the inbreeding coefficient of Wright, (1943) will be designated as F.…”