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Y Rumpler

Publications and source records attributed to Y Rumpler.

120 records · Page 7Linked to original sources
PubMedDate not supplied

XY-quadrivalent association and sterility in a man carrier of a reciprocal autosomal translocation involving the whole arm of an acrocentric chromosome t(2;15)(q21.3;cen).

Meiotic and synaptonemal complex studies using electron microscopy were carried out on an infertile man with a 46,XY t(2q;15p). Synaptonemal complex analysis showed terminal asynapsis in the totality of quadrivalents and a high and significant frequency of association with the XY vesicle (80%), possibly related to the high amount of satellite DNA of the acrocentric chromosome 15. In this translocation carrier, the XY quadrivalent association at pachytene stage is positively correlated with the degree of spermatogenic breakdown after pachytene stage. Whether association with the non-paired segment represents the causative factor or only a secondary effect has still to be clarified.

Adult↗
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Cytogenetic arguments in favour of a taxonomic revision of Lepilemur septentrionalis.

Cytogenetic investigations performed on 30 specimens of Lepilemur septentrionalis confirmed the existence of 4 karyotypes differing from each other by 1-2 chromosomal rearrangements. These data, pooled with those obtained in earlier studies, showed that out of 60 animals karyotyped only two kinds of hybrids were detected, allowing us to characterise two chromosomally polymorphic populations. No natural hybrids could be found between these two populations, which could thus be considered as two separate species. The possible role of the chromosomal rearrangements in the process of reproductive isolation between these two populations is discussed.

Animals↗
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Robertsonian heterozygosity and male sterility.

Meiotic and synaptonemal complex studies using electron microscopy were carried out on infertile man with a 13/14 translocation. Synaptonemal complex analysis showed a typical trivalent with incomplete pairing of the acrocentric elements. The sterilizing effect caused by the failure of synapsis is discussed. This pairing failure has a diagnostic value and a poor prognosis.

Adult↗
PubMedDate not supplied

Double heterozygosity of chromosomal inversion in mice: a key to speciation.

Inversion can be very efficient as a reproductive barrier when the same chromosomes are involved in two different rearrangements leading to a double loop during the pachytene stage. The consequence can be a strongly reduced fertility of the double heterozygotes, leading to an irreversible dichotomy.

Animals↗