Robertsonian karyotype variation in wild house mice from Rhaeto-Lombardia

Gropp, A.; Winking, Heinz; Redi, Carlo Alberto; Capanna, Ernesto; Britton‐Davidian, Janice; Noack, G.

doi:10.1159/000131794

Cited by 97 publications

(81 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…C. Hauffe, unpublished data). Along this short stretch of river valley, we have not only found the Upper Valtellina and Poschiavo karyotypic forms, we have also located the previously described 22-chromosome Lower Valtellina form (Gropp et al 1982), the 40-chromosome standard race and a new 24-chromosome ' Mid Valtellina ' form (Hauffe & Searle 1993). From the karyotypes that we have observed in the field, it is evident that, within the valley as a whole, all the karyotypic forms are hybridizing with each other (in fact we consider the Mid Valtellina form a product of hybridization ; Hauffe & Searle 1993).…”

Section: Introductionsupporting

confidence: 65%

“…However, in nature, the situation is rather complex. It was demonstrated by Gropp, Capanna and co-workers that in addition to the 26-chromosome form in Poschiavo there is a 24-chromosome form in Upper Valtellina (Capanna & Corti 1982 ;Gropp et al 1982). Both forms were found together at high frequencies (60 % : 40 %) in the Upper Valtellina village of Migiondo, but despite a large sample of 150 mice from the settlement, no hybrids were found (Capanna & Corti 1982 ;Mainardi et al 1986).…”

Section: Introductionmentioning

confidence: 99%

“…The tobacco mouse coloration was recorded on mice of a variety of karyotypes (Hauffe 1993) and is known to merely reflect a single dominant allele (E tob ) at the extension locus (Lyon et al 1996). Thus, like Gropp et al (1982), we consider it appropriate that the karyotypic forms within Val Poschiavo\Upper Valtellina should be classified as ' karyotypic races ' (Poschiavo, Upper Valtellina, Lower Valtellina, Mid Valtellina and standard races ; Hauffe & Searle 1993) and that the designation ' Mus poschia inus ' for the Poschiavo race is inappropriate.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Genetic distinctiveness of a village population of house mice: relevance to speciation and chromosomal evolution

Fraguedakis-Tsolis

Hauffe²,

Searle

1997

Proc. R. Soc. Lond. B

View full text Add to dashboard Cite

SUMMARYA population of house mice, Mus musculus domesticus, from the village of Migiondo was found to be genetically distinct from nearby populations in Upper Valtellina (Italian Alps). At the supernatant malic enzyme locus, Mod1, the only alleles found in Migiondo (c and n2) were virtually absent from the other populations in the valley, which were characterized by allele a. The extraordinary genetic distinctiveness of the Migiondo population is apparently the result of genetic drift, perhaps coupled with a founder event, and attests to the existence of nearly impenetrable geographic barriers around the village isolating it from other settlements only a few hundred metres away. The Mod1 features of the house mice in Migiondo are reminiscent of the characteristics of house mice on maritime islands. The genetic confirmation of the geographic isolation of Migiondo is of interest because there is evidence that this village may have been the site of recent speciation and extinction events. The data are also of significance given the phenomenal chromosomal variation in house mice from the vicinity of the Alps. It has frequently been proposed that genetic drift\founder events are of importance in the fixation of chromosomal rearrangements ; this study provides the first direct evidence for their occurrence in alpine mouse populations.

show abstract

Section: Introductionsupporting

confidence: 65%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Genetic distinctiveness of a village population of house mice: relevance to speciation and chromosomal evolution

Fraguedakis-Tsolis

Hauffe²,

Searle

1997

Proc. R. Soc. Lond. B

View full text Add to dashboard Cite

show abstract

“…Here, we compare the molecular organization of pericentromeric regions of telocentrics and Rb chromosomes derived from wild mice of two chromosome races in northern Italy, the Poschiavo and Cremona races (18). We first re-examined the polarity of major satDNA by using the chromosome-orientation fluorescence in situ hybridization (CO-FISH) technique (19).…”

mentioning

confidence: 99%

Pericentromeric organization at the fusion point of mouse Robertsonian translocation chromosomes

Garagna

Marziliano

Zuccotti

et al. 2001

Proc. Natl. Acad. Sci. U.S.A.

116

106

View full text Add to dashboard Cite

In mammals, Robertsonian (Rb) translocation (the joining of two telo͞acrocentric chromosomes at their centromere to form a metacentric) is the most effective process in chromosomal evolution leading to speciation; its occurrence also affects human health (through the induction of trisomies) and the fertility of farm animals. To understand the mechanism of Rb translocation, we used the house mouse as a model system and studied the organization of pericentromeric satellite DNAs (satDNA) of telocentrics and Rb chromosomes, both minor and major satDNA. The chromosome-orientation fluorescence in situ hybridization (CO-FISH) technique was used to analyze the major satDNA. To detect the very small amount of minor satDNA, a procedure was developed that combines CO-FISH with primed in situ labeling and conventional FISH and is five times more sensitive than the CO-FISH procedure alone. It was found that both the major and the minor satDNA tandem repeats are oriented head-to-tail in telocentric and Rb chromosomes, and their polarity is always the same relative to the centromere. We suggest that all tandemly repetitive satDNAs in a species probably are locked into such a symmetry constraint as a universal consequence of chromosomal evolution. Rb translocation breakpoints were found localized within the minor satDNA of telocentrics, and these sequences contributed symmetrically to the formation of the centromeric region of the Rb chromosomes. These results are important for an understanding of the geometry of Rb translocations and suggest the study of DNA orientation as a new tool for investigating these rearrangements.

show abstract

“…The study of natural populations of M. m. domesticus in northern Italy (Capanna 1982;Capanna and Corti 1982;Gropp et al 1982) provides another example of fixation of intermediate karyotypes in a hybrid zone. In a small region of the Phaetian Alps, numerous chromosome races ranging in diploid number from 2n ϭ 26 to 2n ϭ 40 were found.…”

Section: Discussionmentioning

confidence: 99%

STAGGERED CLINES IN A HYBRID ZONE BETWEEN TWO CHROMOSOME RACES OF THE HARVESTMANGAGRELLOPSIS NODULIFERA(ARACHNIDA: OPILIONES)

Gorlov

Tsurusaki

2000

Evolution

View full text Add to dashboard Cite

Abstract. We analyzed a hybrid zone between two chromosome races (2n ϭ 16 and 2n ϭ 22) of a Japanese harvestman, Gagrellopsis nodulifera Sato and Suzuki (Arachnida: Opiliones: Phalangiidae). The hybrid zone is located in the eastern part of Tottori Prefecture, western Honshu. The width of the zone is approximately 5 to 15 km. Three independent tandem fusions/fissions seem to be the main cause of the karyotypic differences between the parental races. Ten karyotypic variants were found in the hybrid zone. They differed by numbers of diploid chromosomes and trivalents detected in meiosis. In most of the collecting sites, karyotypic heterozygotes were less common than expected. A positive correlation was found between number of trivalents in a karyotype and its deficiency rate. In some sites, the deficit of heterozygous individuals was accompanied by an excess of the intermediate homozygotes. One of the three transects across the zone was studied in detail. We found that three types of single heterozygotes (2n ϭ 17, 2n ϭ 19 and 2n ϭ 21) formed a series of successive, spatially separated peaks along the transect. Two types of intermediate homozygotes (2n ϭ 18 and 2n ϭ 20) were also spatially separated. The most parsimonious explanation of such a structure is the staggering of clines of three tandem (or Robertsonian) fusion/fission variants that differentiate the parental races caused by selection against multiple heterozygotes. Analysis of nondisjunction in single heterozygotes demonstrated that there was a strong interindividual variation in nondisjunction rate. The mean frequency of aneuploid MII in single heterozygotes was 0.10 Ϯ 0.03. Crossover exchanges in some critical regions of trivalents result in abnormal chromosomal configurations: chromosomes with unequal chromatids and dicentric chromosomes. Frequency of crossover-induced chromosomal abnormalities was low in single heterozygotes (Ӎ 4%), and was unexpectedly high in the double heterozygotes (Ӎ 15%). Selection against karyotypic heterozygotes is considered as a main evolutionary force responsible for the structuring of the hybrid zone. A positive association between diploid chromosome number and altitude was found. The race 2n ϭ 16 tended to occupy lower altitudes than the 2n ϭ 22 parental race. Differences in ecological preferences may be a result of previous adaptations to different environments in allopatry. A hypothesis concerning the origin and evolution of the hybrid zone is proposed.

show abstract

Robertsonian karyotype variation in wild house mice from Rhaeto-Lombardia

Cited by 97 publications

References 5 publications

Genetic distinctiveness of a village population of house mice: relevance to speciation and chromosomal evolution

Genetic distinctiveness of a village population of house mice: relevance to speciation and chromosomal evolution

Pericentromeric organization at the fusion point of mouse Robertsonian translocation chromosomes

STAGGERED CLINES IN A HYBRID ZONE BETWEEN TWO CHROMOSOME RACES OF THE HARVESTMANGAGRELLOPSIS NODULIFERA(ARACHNIDA: OPILIONES)

Contact Info

Product

Resources

About