PubMed Health⌕ Search

Biomedical subjects

V Ferrier

Publications and source records attributed to V Ferrier.

25 records · Page 2Linked to original sources

Induction of triploidy in the newt Pleurodeles waltlii by heat shock or hydrostatic pressure: interpretation of the different types of ploidy using a chromosomal marker.

Eggs of diploid females of Pleurodeles waltii, fertilized artificially by waltlii sperm, have been submitted to increased temperature of hydrostatic pressure during the first hour of development. Of the resulting viable individuals about 95% were triploid, the remainder diploid or tetraploid. Other types of ploidy have been observed in abnormal embryos (n, 2n/4n, 5n, n/5n, 6n). Some of the treated eggs came from females with a marker chromosome (pericentric inversion). The karyotypes of the animals developing from such eggs confirm that triploidy results from retention of the second polar body and make it possible to interpret the origin of the other types of ploidy. From the results it can be envisaged how gynogenetic animals can be obtained from eggs inseminated by inactivated sperm and shock-treated to restore diploidy.

Aneuploidy↗

Experimental gynogenesis in the newt species Pleurodeles waltlii and P. poireti.

Eggs of diploid females of Pleurodeles waltlii, inseminated by genetically inactivated sperm of Salamandra salamandra, have been treated by heat-shock or increased hydrostatic pressure during the first hour of their development. The resulting viable gynogenetic individuals show different degrees of ploidy although they mostly are diploid. The use of females with a pericentric inversion as a marker chromosome allow the chromosomal constitution to be clarified. Eggs of females heterozygous for a recessive semilethal mutation (ascite caudale, ac) subjected to the same experimental treatment gave 50% ac/ac embryos. Experiments with Pleurodeles poireti gave the same results as those with P. waltlii. These observations prove that gynogenetic Urodeles can be produced in large numbers. In their offspring the detection of inherent or spontaneous recessive mutations is greatly facilitated.

Aneuploidy↗