Biomaterial Database

Evolutionary history of microsatellites in the obscura group of Drosophila. 2001

M A Noor, and R M Kliman, and C A Machado

Department of Biological Sciences, Louisiana State University, Baton Rouge 70803, USA. mnoor@lsu.edu

The evolutionary origins of microsatellites are not well understood. Some investigators have suggested that point mutations that expand repeat arrays beyond a threshold size trigger microsatellites to become variable. However, little empirical data has been brought forth on this and related issues. In this study, we examine the evolutionary history of microsatellites in six species within the obscura group of Drosophila, tracing changes in microsatellite alleles using both PCR product size and sequence data. We found little evidence supporting a general role of point mutations triggering initial microsatellite expansion, and no consistent threshold size for expansion was observed. Flanking region length variation was extensive when alleles were sequenced in distantly related species, and some species possessed altogether different repeat arrays between the same primer binding sites. Our results suggest extreme caution in using microsatellite allele sizes for phylogenetic analyses or to infer divergences between populations.

UI	MeSH Term	Description	Entries
D008969	Molecular Sequence Data	Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.	Sequence Data, Molecular,Molecular Sequencing Data,Data, Molecular Sequence,Data, Molecular Sequencing,Sequencing Data, Molecular
D010802	Phylogeny	The relationships of groups of organisms as reflected by their genetic makeup.	Community Phylogenetics,Molecular Phylogenetics,Phylogenetic Analyses,Phylogenetic Analysis,Phylogenetic Clustering,Phylogenetic Comparative Analysis,Phylogenetic Comparative Methods,Phylogenetic Distance,Phylogenetic Generalized Least Squares,Phylogenetic Groups,Phylogenetic Incongruence,Phylogenetic Inference,Phylogenetic Networks,Phylogenetic Reconstruction,Phylogenetic Relatedness,Phylogenetic Relationships,Phylogenetic Signal,Phylogenetic Structure,Phylogenetic Tree,Phylogenetic Trees,Phylogenomics,Analyse, Phylogenetic,Analysis, Phylogenetic,Analysis, Phylogenetic Comparative,Clustering, Phylogenetic,Community Phylogenetic,Comparative Analysis, Phylogenetic,Comparative Method, Phylogenetic,Distance, Phylogenetic,Group, Phylogenetic,Incongruence, Phylogenetic,Inference, Phylogenetic,Method, Phylogenetic Comparative,Molecular Phylogenetic,Network, Phylogenetic,Phylogenetic Analyse,Phylogenetic Clusterings,Phylogenetic Comparative Analyses,Phylogenetic Comparative Method,Phylogenetic Distances,Phylogenetic Group,Phylogenetic Incongruences,Phylogenetic Inferences,Phylogenetic Network,Phylogenetic Reconstructions,Phylogenetic Relatednesses,Phylogenetic Relationship,Phylogenetic Signals,Phylogenetic Structures,Phylogenetic, Community,Phylogenetic, Molecular,Phylogenies,Phylogenomic,Reconstruction, Phylogenetic,Relatedness, Phylogenetic,Relationship, Phylogenetic,Signal, Phylogenetic,Structure, Phylogenetic,Tree, Phylogenetic
D011110	Polymorphism, Genetic	The regular and simultaneous occurrence in a single interbreeding population of two or more discontinuous genotypes. The concept includes differences in genotypes ranging in size from a single nucleotide site (POLYMORPHISM, SINGLE NUCLEOTIDE) to large nucleotide sequences visible at a chromosomal level.	Gene Polymorphism,Genetic Polymorphism,Polymorphism (Genetics),Genetic Polymorphisms,Gene Polymorphisms,Polymorphism, Gene,Polymorphisms (Genetics),Polymorphisms, Gene,Polymorphisms, Genetic
D004331	Drosophila melanogaster	A species of fruit fly frequently used in genetics because of the large size of its chromosomes.	D. melanogaster,Drosophila melanogasters,melanogaster, Drosophila
D000483	Alleles	Variant forms of the same gene, occupying the same locus on homologous CHROMOSOMES, and governing the variants in production of the same gene product.	Allelomorphs,Allele,Allelomorph
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D016133	Polymerase Chain Reaction	In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.	Anchored PCR,Inverse PCR,Nested PCR,PCR,Anchored Polymerase Chain Reaction,Inverse Polymerase Chain Reaction,Nested Polymerase Chain Reaction,PCR, Anchored,PCR, Inverse,PCR, Nested,Polymerase Chain Reactions,Reaction, Polymerase Chain,Reactions, Polymerase Chain
D018895	Microsatellite Repeats	A variety of simple repeat sequences that are distributed throughout the GENOME. They are characterized by a short repeat unit of 2-8 basepairs that is repeated up to 100 times. They are also known as short tandem repeats (STRs).	Microsatellite Markers,Pentanucleotide Repeats,Simple Repetitive Sequence,Tetranucleotide Repeats,Microsatellites,Short Tandem Repeats,Simple Sequence Repeats,Marker, Microsatellite,Markers, Microsatellite,Microsatellite,Microsatellite Marker,Microsatellite Repeat,Pentanucleotide Repeat,Repeat, Microsatellite,Repeat, Pentanucleotide,Repeat, Short Tandem,Repeat, Simple Sequence,Repeat, Tetranucleotide,Repeats, Microsatellite,Repeats, Pentanucleotide,Repeats, Short Tandem,Repeats, Simple Sequence,Repeats, Tetranucleotide,Repetitive Sequence, Simple,Repetitive Sequences, Simple,Sequence Repeat, Simple,Sequence Repeats, Simple,Sequence, Simple Repetitive,Sequences, Simple Repetitive,Short Tandem Repeat,Simple Repetitive Sequences,Simple Sequence Repeat,Tandem Repeat, Short,Tandem Repeats, Short,Tetranucleotide Repeat
D019143	Evolution, Molecular	The process of cumulative change at the level of DNA; RNA; and PROTEINS, over successive generations.	Molecular Evolution,Genetic Evolution,Evolution, Genetic