The cytogenetic interactions in maize x Tripsacum hybrid derivatives can be remarkably complex. The number of viable, somewhat female fertile chromosome combinations is astonishing. Fifty-four different combinations are listed in this paper, and others are certainly possible. In successive backcrosses to maize, chromosome numbers scale both up and down with ease, sometimes stabilizing for a few...

BACKGROUND Primary lymphoedema is a rare genetic disorder characterized by swelling of different parts of the body and highly heterogenic clinical presentation. Mutations in several causative genes characterize specific forms of the disease. FOXC2 mutations are associated with lymphoedema of lower extremities, usually distichiasis and late onset. PATIENTS AND METHODS Subjects from three gener...

Provided with lunch by his ever-present assistant Nancy, a cooler placed between Dr. Murray and his wife Bobby, both sitting in the rear of the car, we were on our way to rural Maine. Escorted by Ginny, the oldest of the six Murray children who had also been close to the Herricks, we arrived four hours later. Although the event was sad, Cynthia, Ron’s widow, and the extended Herrick family gave...

As part of a series of studies investigating the genetic basis of prolificacy in the non-inbred QS strain of mice, a line has been selected for increased average litter size over the first 5 litters, and seven sublines have been created by full-sib inbreeding with selection for litter size. Six generations of selection have resulted in an increase of average litter size from 16.0 to 18.1, indic...

1. The rate of growth of fibroblasts is markedly modified by slight changes in the hydrogen ion concentration of the medium. The curves expressing the rate of growth in function of the hydrogen ion concentration of the medium are nearly symmetrical on both sides of the maximum. 2. The optimum growth of fibroblasts occurs at pH 7.4 to 7.8. A slight change from this reaction has a remarkable infl...

The genetics of’ salinity tolerance in rice was studied by visual scoring in parents F1 F2 and backcross generations of six crosses. Segregation analysis indicated partial dominance for salinity tolerance. Estimation of genetic parameters under epistatic model indicated the importance of additive effects in the inheritance of salinity tolerance. Highly significant additive type of gene action i...

Optimal transformation of Azotobacter vinelandii OP required a 20-min incubation of the competent cells with deoxyribonucleic acid at 30 degrees C in buffer (pH 6.0 to 8.0) containing 8 mM magnesium sulfate. Nitrogen-fixing transformants of nitrogen fixation-deficient recipients could be plated immediately on selective medium, but transformants acquiring rifampin and streptomycin resistance req...

79 Abstract: Experimental cages started with a mixture of flies at three different ratios (1:9, 5:5, 9:1) from populations having heterosomal and autosomal sex–determining mechanisms were cytogenetically examined over six generations at two different temperatures (25 °C and 35 °C). In general, there was an increase in the frequency of XX males in all competitive population cages. Abnormal teste...

The recognition and catalytic properties of biopolymers derive from an elegant evolutionary mechanism, whereby the genetic material encoding molecules with superior functional attributes survives a selective pressure and is propagated to subsequent generations. This process is routinely mimicked in vitro to generate nucleic-acid or peptide ligands and catalysts. Recent advances in DNA-programme...

Dense masses of spores of Dictyostelium mucoroides var. stoloniferum have the ability to germinate and aggregate rapidly in the absence of food. This is made possible by the presence of a dominant, self-produced spore germination activator. The germination-aggregation cycle can be repeated in as many as six successive generations. In each generation the spore size is reduced so that ultimately ...