Biomaterial Database

Efficient multiplex simple sequence repeat genotyping of the oomycete plant pathogen Phytophthora infestans. 2013

Ying Li, and David E L Cooke, and Evert Jacobsen, and Theo van der Lee

Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.

Genotyping is fundamental to population analysis. To accommodate fast, accurate and cost-effective genotyping, a one-step multiplex PCR method employing twelve simple sequence repeat (SSR) markers was developed for high-throughput screening of Phytophthora infestans populations worldwide. The SSR markers reported for this species were evaluated and the twelve most informative and easily scored were selected. To accomplish a single step genotyping procedure, we optimized primers, fluorescent labels and PCR conditions to genotype using a capillary electrophoresis system with four fluorescent labels (FAM, NED, PET and VIC) and a labeled LIZ standard for sizing of the SSR fragments. The results obtained using commercially available multiplex PCR kits on a set of reference isolates were in agreement with that obtained using primer pairs in simplex reactions. In testing on many thousands of isolates, we have found the markers appropriate for resolving distinct multilocus genotypes (MLGs) of isolates of European and wider populations. Here we demonstrate the utility of the assay on a set of 19 reference isolates plus 77 others sampled from The Netherlands and Great Britain. In most isolates one to two alleles were observed at each locus but the presence of three alleles at a single locus in some isolates was consistent with increased ploidy. Methods are presented that are appropriate for the analysis of datasets comprising isolates of mixed ploidy levels. We also report on the direct P. infestans genotyping from infected field material to collect, store and extract pathogen DNA. A critical step in this multiplex method was the standardization of the protocol between two laboratories in The Netherlands and Great Britain. Reference isolates were exchanged and an allele nomenclature and scoring system agreed. Such co-operation is facilitating the genotyping of international collections of P. infestans isolates in wider networks of laboratories and providing the data required to expand an existing international database of pathogen diversity.

UI	MeSH Term	Description	Entries
D009426	Netherlands	Country located in EUROPE. It is bordered by the NORTH SEA, BELGIUM, and GERMANY. Constituent areas are Aruba, Curacao, and Sint Maarten, formerly included in the NETHERLANDS ANTILLES.	Holland,Kingdom of the Netherlands
D010935	Plant Diseases	Diseases of plants.	Disease, Plant,Diseases, Plant,Plant Disease
D005838	Genotype	The genetic constitution of the individual, comprising the ALLELES present at each GENETIC LOCUS.	Genogroup,Genogroups,Genotypes
D006113	United Kingdom	Country in northwestern Europe including Great Britain and the northern one-sixth of the island of Ireland, located between the North Sea and north Atlantic Ocean. The capital is London.	Great Britain,Isle of Man
D055750	Phytophthora infestans	A species of parasitic OOMYCETES in the family Peronosporaceae that is the causative agent of late blight of potato.	Phytophthora infestan,infestans, Phytophthora
D058889	Molecular Typing	Using MOLECULAR BIOLOGY techniques, such as DNA SEQUENCE ANALYSIS; PULSED-FIELD GEL ELECTROPHORESIS; and DNA FINGERPRINTING, to identify, classify, and compare organisms and their subtypes.	Typing, Molecular
D060885	Multiplex Polymerase Chain Reaction	Methods for using more than one primer set in a polymerase chain reaction to amplify more than one segment of the target DNA sequence in a single reaction.	Multiplex Ligation-Dependent Probe Amplification,Multiplex PCR,Triplex PCR,Triplex Polymerase Chain Reaction,Multiplex Ligation Dependent Probe Amplification,PCR, Multiplex,PCR, Triplex
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
D019075	Electrophoresis, Capillary	A highly-sensitive (in the picomolar range, which is 10,000-fold more sensitive than conventional electrophoresis) and efficient technique that allows separation of PROTEINS; NUCLEIC ACIDS; and CARBOHYDRATES. (Segen, Dictionary of Modern Medicine, 1992)	Capillary Zone Electrophoresis,Capillary Electrophoreses,Capillary Electrophoresis,Capillary Zone Electrophoreses,Electrophoreses, Capillary,Electrophoreses, Capillary Zone,Electrophoresis, Capillary Zone,Zone Electrophoreses, Capillary,Zone Electrophoresis, Capillary