Biomaterial Database

Gene segregation in induced tetraploid rainbow trout: genetic evidence of preferential pairing of homologous chromosomes. 1988

A Diter, and R Guyomard, and D Chourrout

Laboratoire de génétique des poissons, Institut national de la recherche agronomique, Jouy-en-Josas, France.

Gene segregation at six protein loci was analysed in progeny from tetraploid males and females obtained by suppression of first mitosis. The triploid full-sib families from five tetraploid males and the diploid gynogenetic lines from four tetraploid females were examined. The proportions of heterozygous gametes (0.83 on the average) were significantly higher than expected from tetrasomic inheritance (0.667) at all the loci studied. This was explained by preferential pairing of homologous chromosomes. The proportions of heterozygous gametes were significantly different between loci, but the variations were not correlated with the gene--centromere distances. Our results showed that, at least for one locus, the homozygous gametes mainly resulted from pairing of homologous chromosomes rather than from pairing of homologous chromosomes, quadrivalent formation, and chromatin exchanges between homologous chromosomes.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D011123	Polyploidy	The chromosomal constitution of a cell containing multiples of the normal number of CHROMOSOMES; includes triploidy (symbol: 3N), tetraploidy (symbol: 4N), etc.	Polyploid,Polyploid Cell,Cell, Polyploid,Cells, Polyploid,Polyploid Cells,Polyploidies,Polyploids
D011506	Proteins	Linear POLYPEPTIDES that are synthesized on RIBOSOMES and may be further modified, crosslinked, cleaved, or assembled into complex proteins with several subunits. The specific sequence of AMINO ACIDS determines the shape the polypeptide will take, during PROTEIN FOLDING, and the function of the protein.	Gene Products, Protein,Gene Proteins,Protein,Protein Gene Products,Proteins, Gene
D002875	Chromosomes	In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Chromosome
D003433	Crosses, Genetic	Deliberate breeding of two different individuals that results in offspring that carry part of the genetic material of each parent. The parent organisms must be genetically compatible and may be from different varieties or closely related species.	Cross, Genetic,Genetic Cross,Genetic Crosses
D005260	Female		Females
D005306	Fertilization	The fusion of a spermatozoon (SPERMATOZOA) with an OVUM thus resulting in the formation of a ZYGOTE.	Conception,Fertilization, Delayed,Fertilization, Polyspermic,Conceptions,Delayed Fertilization,Delayed Fertilizations,Fertilizations,Fertilizations, Delayed,Fertilizations, Polyspermic,Polyspermic Fertilization,Polyspermic Fertilizations
D005796	Genes	A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms.	Cistron,Gene,Genetic Materials,Cistrons,Genetic Material,Material, Genetic,Materials, Genetic
D006580	Genetic Carrier Screening	Identification of individuals who are heterozygous at a GENETIC LOCUS for a recessive PHENOTYPE.	Carriers, Genetic, Detection,Genetic Carriers, Detection,Heterozygote Detection,Carrier Detection, Genetic,Detection, Genetic Carrier,Genetic Carrier Detection,Heterozygote Screening,Carrier Screening, Genetic,Detection, Heterozygote,Screening, Genetic Carrier,Screening, Heterozygote,Screenings, Genetic Carrier
D006720	Homozygote	An individual in which both alleles at a given locus are identical.	Homozygotes