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1.
Genetics ; 144(1): 139-46, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8878680

RESUMO

Twenty-two markers located on Muller's elements D or E have been mapped by in situ hybridization in six species of the obscura group of Drosophila and in D. melanogaster. The obscura species can be grouped into a Palearctic cluster (D. subobscura, D. madeirensis and D. guanche) and a Nearctic one (D. pseudoobscura, D. persimilis and D. miranda). Eleven of the probes contain known genes: E74, Acp70A, Est5, hsp28/23, hsp83, emc, hsp70, Xdh, Acph-1, Cec and rp49. The remaining probes are recombinant phages isolated from a D. subobscura genomic library. All these markers hybridize to the putative homologous chromosome or chromosomal arm of elements D and E. Thus, these elements have conserved their genic content during species divergence. Chromosomal homologies proposed previously for each element among the species of the same cluster have been compared with the present results. The distribution of markers within each element has changed considerably as inferred from pairwise comparisons of obscura species included in the two different clusters. Only chromosomal segments defined by closely linked markers have been conserved: one such segment has been detected in element D and three in element E between D subobscura and D. pseudoobscura.


Assuntos
Drosophila melanogaster/genética , Drosophila/genética , Genes de Insetos , Animais , Marcadores Genéticos
2.
Genetics ; 151(1): 189-202, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9872959

RESUMO

Nucleotide variation at the ribosomal protein 49 (rp49) gene region has been studied in 75 lines of Drosophila subobscura belonging to four chromosomal arrangements (Ost, O3+4, O3+4+8, and O3+4+23). The location of the rp49 gene region within the inversion loop differs among heterokaryotypes: it is very close to one of the breakpoints in heterozygotes involving Ost chromosomes, while it is in a more central position in all other heterokaryotypes. The distribution of nucleotide polymorphism in the different arrangements is consistent with a monophyletic origin of the inversions. The data also provide evidence that gene conversion and possibly double crossover are involved in shuffling nucleotide variation among gene arrangements. The analyses reveal that the level of genetic exchange is higher when the region is located in a more central position of the inverted fragment than when it is close to the breakpoints. The pairwise difference distributions as well as the negative values of Tajima's and Fu and Li's statistics further support the hypothesis that nucleotide variation within chromosomal arrangements still reflects expansion after the origin of the inversions. Under the expansion model, we have estimated the time of origin of the studied inversions.


Assuntos
Inversão Cromossômica , Proteínas de Drosophila , Drosophila/genética , Proteínas de Insetos/genética , Proteínas Ribossômicas/genética , Animais , Sequência de Bases , DNA Complementar , Drosophila/classificação , Variação Genética , Dados de Sequência Molecular , Filogenia
3.
Hum Hered ; 42(2): 146-8, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1572674

RESUMO

The distribution of transferrin (TF) subtypes was determined by isoelectric focusing of sera from 284 unrelated individuals from Tarragona (south of Catalonia). The allele frequencies observed, TF*C1 = 0.805, TF*C2 = 0.162, TF*C3 = 0.026 and TF*B = 0.007 were similar to those reported for other Spanish populations.


Assuntos
Genética Populacional , Transferrina/genética , Alelos , Frequência do Gene/genética , Humanos , Fenótipo , Espanha
4.
Hum Hered ; 39(3): 182-4, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2591982

RESUMO

The red blood cell esterase D (ESD) polymorphism was studied by means of IEF in a North-East Spanish population (Barcelona). Gene frequencies in 430 unrelated individuals were ESD*1: 0.888, ESD*2: 0.091 and ESD*5: 0.021. Our data confirm previous results showing that ESD*5 occurs in polymorphic frequency and has a Caucasian origin.


Assuntos
Carboxilesterase , Hidrolases de Éster Carboxílico/genética , Frequência do Gene , Humanos , Focalização Isoelétrica , Fenótipo , Polimorfismo Genético , Espanha
5.
Hum Hered ; 38(1): 62-3, 1988.
Artigo em Inglês | MEDLINE | ID: mdl-3350535

RESUMO

Blood samples from two Catalonian populations (North-East of Spain) were analysed for glyoxalase (GLO) I polymorphism. Gene frequencies of GLO1 (0.46 and 0.41) are comparable to those reported for Central-European Caucasoid populations.


Assuntos
Lactoilglutationa Liase/genética , Liases/genética , Eritrócitos/enzimologia , Frequência do Gene , Genética Populacional , Humanos , Polimorfismo Genético , Espanha
6.
Heredity (Edinb) ; 63 ( Pt 2): 195-202, 1989 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2509403

RESUMO

The effect of larval density on male mating success has been investigated with two strains of Drosophila melanogaster, a wild strain and a mutant strain, under low and high larval competition, and four different genotypic frequencies. The results show a strong sexual selection against mutant males when flies have been raised under low larval competition. Under high larval competition, there is a reduction in mating disadvantage of mutant males. In both instances, a frequency-dependent sexual selection exists. These results explain adequately the evolution of experimental populations where egg to adult viability and male mating success are the most important components of fitness.


Assuntos
Aglomeração , Drosophila melanogaster/genética , Comportamento Sexual Animal , Alelos , Animais , Cor de Olho , Feminino , Frequência do Gene , Larva/genética , Masculino , Mutação , Seleção Genética
7.
Genetica ; 80(1): 39-43, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2323564

RESUMO

Eleven populations of Drosophila subobscura that had been maintained in laboratory conditions during different periods of time were examined for evidence of genetic divergence in mating activity. The results indicate that mating activity increases with the time of maintenance under laboratory conditions.


Assuntos
Drosophila/genética , Comportamento Sexual Animal , Animais , Animais de Laboratório/genética , Feminino , Masculino
8.
Proc Natl Acad Sci U S A ; 85(15): 5597-600, 1988 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16593967

RESUMO

North America and South America have recently been colonized by the Palearctic species Drosophila subobscura. This double colonization offers a rare opportunity for evolutionary studies. Correlations between chromosomal arrangement frequencies and latitude were calculated for the colonizing populations. Signs of these correlations are highly coincident with those found in the Old World. These results provide experimental support for the adaptive value of the chromosomal-inversion polymorphism; historical and other nonadaptive explanations are thus excluded or relegated to a secondary role.

9.
Chromosoma ; 104(2): 129-36, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8585990

RESUMO

Thirty P1 clones from the X chromosome (Muller's A element) of Drosophila melanogaster were cross-hybridized in situ to Drosophila subobscura and Drosophila pseudoobscura polytene chromosomes. An additional recombinant phage lambda Dsuby was also used as a marker. Twenty-three (77%) of the P1 clones gave positive hybridization on D. pseudoobscura chromosomes but only 16 (53%) did so with those of D. subobscura. Eight P1 clones gave more than one hybridization signal on D. pseudoobscura and/or D. subobscura chromosomes. All P1 clones and lambda Dsuby hybridized on Muller's A element (X chromosome) of D. subobscura. In contrast, only 18 P1 clones and lambda Dsuby hybridized on Muller's A element (XL chromosomal arm) of D. pseudoobscura; 4 additional P1 clones hybridized on Muller's D element (XR chromosomal arm) of this species and the remaining P1 clone gave one hybridization signal on each arm of the X chromosome. This latter clone may contain one breakpoint of a pericentric inversion that may account for the interchange of genetic material between Muller's A and D elements in D. pseudoobscura. In contrast to the rare interchange of genetic material between chromosomal elements, profound differences in the order and spacing of markers were detected between D. melanogaster, D. pseudoobscura and D. subobscura. In fact, the number of chromosomal segments delimited by identical markers and conserved between pairwise comparisons is small. Therefore, extensive reorganization within Muller's A element has been produced during the divergence of the three species. Rough estimates of the number of cytologically detectable inversions contributing to differentiation of Muller's A element were obtained. The most reliable of these estimates is that obtained from the D. pseudoobscura and D. melanogaster comparison since a greater number of markers have been mapped in both species. Tentatively, one inversion breakpoint about every 200 kb has been produced and fixed during the divergence of D. pseudoobscura and D. melanogaster.


Assuntos
Mapeamento Cromossômico/métodos , Drosophila/genética , Evolução Molecular , Marcadores Genéticos , Cromossomo X , Animais , Inversão Cromossômica , Clonagem Molecular , Drosophila/classificação , Drosophila melanogaster/genética , Hibridização In Situ
10.
Hum Hered ; 43(4): 219-22, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8344666

RESUMO

A random sample of 1,491 individuals from three Basque provinces was studied for the red-cell esterase D (ESD) polymorphism by means of isoelectric focusing. The following allele frequencies were observed: Vizcaya, ESD*1 = 0.933, ESD*2 = 0.058, ESD*5 = 0.009; Guipuzcoa, ESD*1 = 0.938, ESD*2 = 0.053, ESD*5 = 0.009; and Alava, ESD*1 = 0.894, ESD*2 = 0.088, ESD*5 = 0.018. The Basques from Vizcaya and Guipuzcoa display the lowest values for allele ESD*5 of any European population studied to date. The value obtained for this allele in the Basque population of Alava is significantly higher than those found in the other two Basque samples. This, together with the fact that Basques from Alava display the lowest ESD*1 frequency of any Basque series, suggests that there are genetic differences between Basque provinces.


Assuntos
Carboxilesterase , Hidrolases de Éster Carboxílico/sangue , Etnicidade/genética , Frequência do Gene/genética , Alelos , Hidrolases de Éster Carboxílico/genética , Humanos , Focalização Isoelétrica , Fenótipo , Polimorfismo Genético/genética , Espanha
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