Pairing of X and Y chromosomes, non-inactivation of X-linked genes, and the maleness factor

Polani, P. E.

doi:10.1007/bf00303003

Cited by 100 publications

(48 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This segment is of considerable interest because in this region, a reduction of X inactivation has been observed (Mohandas et al 1979;Miiller et al 1980;Migeon et al 1982). Furthermore, this region is thought to be involved in crossover events with the distal end of the short arm of the Y chromosome (de la Chapelle 1981;Polani 1982;Burgoyne 1982). The hypothesis that the distal ends of the short arms of X and Y are homologous on the molecular level has recently received additional experimental support (Goodfellow and Tippett 1981;Goodfellow et al 1983).…”

Section: Discussionmentioning

confidence: 99%

“…In analogy to meiotic pairing of autosomes, these observations suggest a homology also on the level of DNA. Such a homology is supported by speculations (Haldane 1936;de la Chapelle et al 1981;Polani 1982;Burgoyne 1982) that cross-over does occur between homologous segments of X and Y.…”

Section: Introductionmentioning

confidence: 86%

“…In the prophase of male meiosis of man, pairing occurs between the short arm of the Y and the distal part of the short arm of the X chromosome (Burgoyne 1982;Polani 1982;Solari 1980;Solari and Tres 1970;Moses 1975;Pearson 1970). In analogy to meiotic pairing of autosomes, these observations suggest a homology also on the level of DNA.…”

Section: Introductionmentioning

confidence: 93%

See 2 more Smart Citations

Chromosome assignment of two cloned DNA probes hybridizing predominantly to human sex chromosomes

Rappold

Cremer

et al. 1984

Hum Genet

View full text Add to dashboard Cite

Summary. In situ hybridization experiments were carried out with two clones, YACG35 and 2.8, which had been selected from two genomic libraries strongly enriched for the human Y chromosome. Besides the human Y chromosome, both sequences strongly hybridized to the human X chromosome, with few minor binding sites on autosomes. In particular, on the X chromosome DNA from clone YACG35 hybridized to the centromeric region and the distal part of the short arm (Xp2.2). On the Y chromosome, the sequence was assigned to one site situated in the border region between Yql.land Yql.2. DNA from clone 2.8 also hybridized to the centromeric region of the X and the distal part of the short arm (Xp2.2). On the Y, however, two binding sites were observed (Ypl.1 and Yql.2). The findings indicate that sex chromosomal sequences may be localized in homologous regions (as suggested from meiotic pairing) but also at ectopic sites.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 86%

See 1 more Smart Citation

Chromosome assignment of two cloned DNA probes hybridizing predominantly to human sex chromosomes

Rappold

Cremer

et al. 1984

Hum Genet

View full text Add to dashboard Cite

show abstract

“…Characterization and chromosomal localization of repetitive and unique sequences located on the Y. It may be assumed (5,10,31,(33)(34)(35) that, for a consider- It has been speculated (5,191 that the Y chromosome may contain a number of genes in addition to those associated with primary sexual development (probably located in the distal part of its short arm (5)). According to these ideas, these genes might take part in crossing over events with homologous X chromosomal regions.…”

Section: Discussionmentioning

confidence: 99%

Preparative dual‐beam sorting of the human Y chromosome and in situ hybridization of cloned DNA probes

Cremer¹,

Rappold²,

Gray³

et al. 1984

Cytometry

View full text Add to dashboard Cite

Bivariate Hoechstkhromomycin flow karyotypes for chromosomes from a Chinese hamster-human hybrid cell line (CH-Y-VII) were established that have retained a human Y chromosome. These bivariate flow karyotypes showed the human Y chromosome to be completely separated from the peaks for the Chinese hamster chromosomes. In preparative dual-beam sorting experiments, 3 x lo6 chromosomes were sorted from the Y peak into frozen petri dishes. An examination of Qbanded samples of sorted chromosomes revealed that 82% * 5% of them were human Y chromosomes.The DNA from the sorted chromosomes (approximately 250 ng) was isolated and used to establish a genomic library (vector X gt WESAB). Three clones (YACG 45, 52, 54) of Genomic libraries representative of the DNA of a specific chromosome (chromosome specific genomic library) may have a wide range of applications; e.g., for an analysis of the correlation of specific genetic traits with polymorphisms of the length of restriction fragments (4, 11,21,32), for establishment of DNA probes specific for particular chromosomes or chromosome regions (32,38), for investigations of tumor-related genetic occurrences (ll), or for studies concerning chromosome evolution (7,25). In principle, such investigations may also be performed using a library of the entire genome; however, the availability of chromosome-specific libraries should considerably facilitate them.The most direct way to construct a chromosome-specific library is to purify the chromosome of interest by fluorescence activated sorting (20) and to establish a genomic library from the DNA of the sorted chromosomes. This approach has recently been used to establish a genomic library for DNA from the X chromosomes this library containing inserts of repetitive human DNA were used for chromosomal localization by means of in situ hybridization to metaphase spreads of male human lymphocytes and of CH-Y-VII cells. In all three cases, a significant binding to the human Y chromosome was observed. A more detailed study of the chromosomal distribution of sequences homologous to the insert of YACG 45 suggested the existence of minor binding sites on several human autosomes. Southern blot analysis revealed the existence of other human specific sequences without Y chromosome specificity.Key terms: Isolated chromosomes, chromosome sorting, genomic libraries, in situ hybridization from man (12) and mouse (261, and from human chromosomes 21 and 22 (22), respectively.In this paper, we report on the preparative dual-beam sorting of the human Y chromosome for the construction of a Y chromosomal genomic library and a characterization of the Y specificity of cloned DNA probes. The human Y chromosomes (in this context also simply referred to as "Y chromosomes") were purified by dualbeam sorting (13,141 from a Chinese hamster-man hybrid cell line retaining the Y as the only free human chromosome (9).

show abstract

“…Since it was (and is) assumed that the mammalian X and Y arose from an ancestral pair of homologues, they concluded that there is a region of homology between the X and Y in all mammalian species and that this region regularly synapses and crosses over during meiosis in a manner analogous to the autosomes. This assumption is still widely accepted (BURGOYNE 1982;POLANI 1982). Indeed, the idea has gained recent momentum from the molecular data for regular exchange of DNA between the X and Y in humans (ROUYER et al 1986).…”

mentioning

confidence: 99%

The behavior during pachynema of a normal and an inverted Y chromosome in Microtus agrestis

2008

View full text Add to dashboard Cite

The pachytene behavior of the chromosomes of Microrus agresris (L.) (Rodentia, Arvicolidae) males carrying either the standard, or the pencentrically inverted Lund Y chromosome have been examined by electron microscopy of microspread spermatocytes. There is no synapsis between the X and either the standard or the Lund Y chromosomes during any substage of pachynema. Since synapsis is generally considered a prerequisite for crossing over, there appears to be no opportunity for crossover or chiasma formation between the X and Y in this species. The G-, C-and NOR-banded mitotic karyotypes of animals carrying the standard and Lund Y are also presented. KOLLER and DARLINGTON (1934) observed a region of synapsis between the X and Y chromosomes of the Norwegian rat during pachynema and end association between them during metaphase I of meiosis. Since it was (and is) assumed that the mammalian X and Y arose from an ancestral pair of homologues, they concluded that there is a region of homology between the X and Y in all mammalian species and that this region regularly synapses and crosses over during meiosis in a manner analogous to the autosomes. This assumption is still widely accepted (BURGOYNE 1982;POLANI 1982). Indeed, the idea has gained recent momentum from the molecular data for regular exchange of DNA between the X and Y in humans (ROUYER et al. 1986). None the less, there is ample evidence that synapsis and subsequent crossover of the X and Y as a mechanism of disjunction of the sex chromosomes is not a universal phenomenon in mammals, or even in eutherians (cf. ASHLEY 1985ASHLEY , 1987 for review).One species which does not fit this general pattern is the Egyptian sand rat (Psammomys obesus), in which there is clearly no synapsis between the X and Y during pachynema (SOLARI and ASHLEY 1977;ASHLEY and MOSES 1980). Since synapsis is generally assumed to be a prerequisite for crossing over, it can be presumed that the asynapsis of the X and Y provides no opportunity for crossover. Consequently, disjunction of the sex chromosomes must be assumed to be achiasmatic in this species. The most prominent feature of the karyotype of the sand rat is formed by large blocks of heterochromatin on both the X and Y. SOLARI and ASHLEY (1977) suggested that this heterochromatin might be involved in an unspecified manner in the asynaptic behavior of the sex chromosomes of this species. It was therefore of interest to determine whether other species with large blocks of heterochromatin on their sex chromosomes are also asynaptic, or whether they synapse with a potential for chiasmatic disjunction. Microtus agrestis, the European field vole, has the distinction of having more constitutive heterochromatin on its sex chromosomes than any other species so far examined. Heterochromatin accounts for approximately 25 YO of the total female haploid genome (Hsu and ARRIGHI 1971;GAMPERL et al. 1982) of which 20 Yo is located on the X chromosome. Approximately three fourths of the submetacentric X is heterochromatic; the rest is euchromati...

show abstract

Pairing of X and Y chromosomes, non-inactivation of X-linked genes, and the maleness factor

Cited by 100 publications

References 29 publications

Chromosome assignment of two cloned DNA probes hybridizing predominantly to human sex chromosomes

Chromosome assignment of two cloned DNA probes hybridizing predominantly to human sex chromosomes

Preparative dual‐beam sorting of the human Y chromosome and in situ hybridization of cloned DNA probes

The behavior during pachynema of a normal and an inverted Y chromosome in Microtus agrestis

Contact Info

Product

Resources

About