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A portion of the Aedes aegypti mitochondrial NADH dehydrogenase subunit 4 gene (ND4) was amplified using PCR with a 42 °C annealing temperature. Amplified fragments from individual mosquitoes were similar to ND4 but contained multiple segregating sites. We suspected that nuclear copies of mitochondrial origin (NUMTs) exist in the Ae. aegypti genome. A BlastN search in VectorBase with the entire Ae. aegypti mitochondrial genome identified 233 NUMTs comprising 110 178 bp in 145 supercontigs. At a density of 0.080 bp/kb, this represents the second highest density of NUMTs in an insect genome and the highest in Diptera. Analyses of flanking sequences suggested that Ae. aegypti NUMTs arise through mtDNA leakage from damaged mitochondria followed by breakage and nonhomologous recombination, rather than through duplicative processes such as transposition or molecular drive. [ABSTRACT FROM AUTHOR]

Genome sizes and the organization of repetitive DNA were determined in the hard ticksIxodes scapularisandBoophilus microplususing reassociation kinetics. TheI. scapularisgenome contains∼2.15 pg (2.1 × 103 Mbp) of DNA and consists of no foldback (FB), 27% highly repetitive (HR), 39% moderately repetitive (MR), and 34% unique DNA. TheB. microplusgenome contains 7.5 pg (7.1 × 103 Mbp) DNA, and consists of 0.82% FB, 31% HR, 38% MR, and 30% unique DNA. In both species, repetitive sequences occur in a mixture of long and short period interspersion but most (65–80%) of the DNA follows a pattern of short period interspersion. Genome size and organization in the three tick species so far examined are distinct from other arthropods in having a greater proportion of MR, a lower proportion of unique and HR DNA of very low sequence complexity. [ABSTRACT FROM AUTHOR]

Abstract Many applications in insect genetics require repeated analyses on individual organisms. These include population genetic and genomics, linkage mapping, molecular systematics and map-based positional cloning. However, using the polymerase chain reaction, a limited number of analyses are possible with DNA isolated from whole bodies or parts of small or preserved specimens. We describe the optimization of a new technique, Multiple Displacement Amplification, for 100–400-fold amplification of whole mosquito genomes. We demonstrate that MDA amplifies genomic DNA directly from an adult leg or from organisms as small as a first instar mosquito larva. Genetic polymorphisms revealed at individual loci are the same whether using the original genomic DNA or MDA DNA as a template. [ABSTRACT FROM AUTHOR]