Nucleotide Polymorphisms (SNPs) are the most common type
of sequence variation and account for about 90% of sequence
differences in humans. Of particular interest are coding
SNPs (cSNPs), which have the potential to alter the coding
sequence of genes and possibly gene functionality. SeqWright
offers customized SNP discovery packages for targeting
and characterizing sequence variations in large numbers.
SNP discovery service is designed to give customers a
complete beginning-to-end solution. Assay development
is accomplished using commercial and proprietary informatics
tools, which align cDNA sequence to genomic sequence and
choose amplicons with corresponding primer sets. Primers
are designed to yield Phred20 data across the entire span
of targeted exon and are manufactured in our DNA synthesis
laboratory. Exons are amplified from genomic DNA, and
resulting PCR products are purified for downstream processing.
Data is collected using fluorescent dye-terminator chemistry
by fully automated ABI 3730xl sequencers. Traces are compiled
into contigs (when applicable) and scored by two independent
observers using Phred base call confidence scores to identify
high probability heterozygotes. Candidate SNPs are validated
by re-sequencing the opposite DNA strand to confirm the
polymorphism. Mapping against public databases is also
available. All work is performed according to GLP and
reviewed by an independent quality assurance (QA) unit.
may enter our SNP discovery pipeline at any point from
assay construction to sequencing. Genotyping is available
for polymorphism verification and heterozygosity determination.
Upon completion of the project, customers will receive
a hardcopy report detailing the project and identifying
all mutations/heterozygotes present in the sequence.
of the service include:
Assay development and validation
· Primer design and synthesis
· PCR amplification and purification
· Automated fluorescent dye-terminator sequencing
· Sequence trace alignment and editing
· In silico mutation/variation identification
· Heterozygosity detection via genotyping
· Hard copy final report