The Genotypic Control of Crossing over in Drosophila Pseudoobscura.

Salivary Gland Chromosomes in the Two Races of Drosophila Pseudoobscura.

The two races of Drosophila pseudoobscura, known as race A and race B, produce sterile male offspring when crossed (LANCEFIELD 1929), have visibly different shapes of the Y chromosomes (DOBZHANSKY and BOCHE 1933), and differ in their physiological characteristics (POULSON 1934, DOBZHANSKY 1935a, BOCHE unpublished). They appear, however, indistinguishable morphologically. LANCEFIELD (1929) and K...

Crossing over in the Sex Chromosome of Racial Hybrids of Drosophila Pseudoobscura.

Repeat mediated gene duplication in the Drosophila pseudoobscura genome.

Genetic mutations can occur on a wide variety of scales, including those that change single nucleotides, those that add or remove content to/from a genome, and those that change the organization of a genome. Gene duplications are a specific class of mutations that add content to a genome, and they can arise via a wide variety of mechanisms. I examined the mechanisms responsible for recently dup...

Some of Drosophila Melanogaster

LL present theories of crossing over tacitly assume that events in one tetA rad (at least as far as crossing over is concerned) are independent of those occurring in the other tetrads of the cell. Yet as long ago as 1919 STURTEVANT suspected that the presence of a heterozygous inversion in one chromosome pair increases crossing over in a non-homologous pair of chromosomes. The effect was defini...

Fine-scale mapping of recombination rate in Drosophila refines its correlation to diversity and divergence.

Regional rates of recombination often correlate with levels of nucleotide diversity, and either selective or neutral hypotheses can explain this relationship. Regional recombination rates also correlate with nucleotide differences between human and chimpanzee, consistent with models where recombination is mutagenic; however, a lack of correlation is observed in the Drosophila melanogaster group...