SNP Genotyping Santiago C. González-Martínez Center of Forest Research, INIA, PO Box Madrid, Spain
Syvänen (2001) Nature Genetics
DGGE and SSCP
(eco)Tilling
Single-base extension
Fluorescence Polarization with Terminator-Dye Incorporation (FP-TDI) - a method for SNP detection
Chen et al Genome Res. Fluorescence polarization
FP-TDI Assay
What the data might look like… if you are lucky Gene 4CL
Usually, the data is not quite as ‘perfect’… Gene EREBPS
FP-TDI ADVANTAGES No special primers Relatively simple procedure Results are immediate DISADVANTAGES Expensive plate reader = $30, 000 kit = $10, 000 for 100, 000x plates = $6 each cost per reaction = 75c each thermocycler maintenance PCR (ie mostly Taq) costs One SNP per reaction Need to know sequence
Pyrosequencing
Microarrays Syvänen (2001) Nature Genetics
High-throughput methods Syvänen 2005 Nature Genetics
Illumina- BeadStation500G-BeadLab Platform
How does it work?
Experimental Procedure
Example of a “nice” SNP
Examples of midrange SNPs Above threshold: GT = Cluster_sep =0.272 Below threshold: GT = Cluster_sep =0.267
4CL-s5[c/t]
AT-s3[g/a] Not resolved with FPBetter separation in Illumina
Illumina- BeadStation demo