Single Nucleotide Polymorphism (SNP) Genotyping

Single Nucleotide Polymorphism (SNP) Genotyping – High‑Throughput, Ultra‑Accurate, and Biologically Interpreted

If you are searching for single nucleotide polymorphism (SNP) genotyping, you likely need to identify specific genetic variants associated with disease risk, pharmacogenomic response, ancestry, or agricultural trait selection. Unlike whole‑genome sequencing, SNP genotyping targets known variable sites with exceptional speed, cost‑efficiency, and statistical power. Our laboratory provides complete SNP genotyping services – from custom assay design and low‑plex verification to high‑density genome‑wide arrays (up to 5 million SNPs), targeted next‑generation sequencing (NGS) panels, and real‑time PCR allelic discrimination – following CLIA, ISO/IEC 17025, and GCP guidelines for research and clinical applications.

What We Genotype – Full SNP Analysis Scope

We do not simply report “homozygous or heterozygous”. Our platform includes TaqMan SNP Genotyping Assays (Thermo Fisher) for low‑ to medium‑plex (1‑500 SNPs) with >99.9% call accuracy and 0.1% detection of minor allele in pooled samples. For high‑throughput screening (thousands to millions of SNPs), we use Illumina Infinium Global Screening Arrays (GSA) and Infinium Omni Express arrays, as well as Affymetrix Axiom arrays, covering human, animal, plant, and microbial genomes. For custom SNP panels, we offer targeted NGS with molecular inversion probes (MIPs) or amplicon‑based enrichment, achieving >99% completeness and >98% concordance with reference. We also perform real‑time PCR allelic discrimination (QuantStudio 12K Flex) with low‑cost, rapid turnaround (2‑4 hours) for up to 384 samples per run. For samples with limited DNA (e.g., FFPE, single cells), we use pre‑amplification and microfluidics (Fluidigm Biomark HD) to genotype from as little as 20 pg of DNA. Our service includes automatic genotype calling (with manual review for ambiguous clusters), Hardy‑Weinberg equilibrium testing, and quality control (call rate, heterozygosity, sample duplicates). For population genetics, association studies, and polygenic risk scores (PRS), we provide imputation using 1000 Genomes, Haplotype Reference Consortium (HRC), or custom reference panels to infer ungenotyped SNPs. Bioinformatics output includes PLINK format files, VCF, and custom annotated Excel reports.

Key parameters and deliverables we routinely provide:
- Genotype calls (AA, AB, BB) with confidence scores (call rate >95% per sample, >98% per SNP).
- Allele frequencies, Hardy‑Weinberg p‑values, and minor allele frequency (MAF).
- Sample call rate and quality metrics (sample Q‑score, heterozygosity) – flagging possible contamination or low‑quality DNA.
- Concordance with reference or replicate samples (typically >99.5%).
- Clustering plots for each SNP (for TaqMan or array data) – visual confirmation of allele separation.
- Imputed genotype probabilities (for untyped SNPs) and imputation quality (Rsq).
- Polygenic risk score (PRS) based on literature weights or custom training set – for research applications.
- Pharmacogenetic reporting (e.g., CYP2C19, CYP2D6, TPMT, DPYD) – with phenotype translation (poor, intermediate, normal, ultrarapid metabolizer).
- Raw data files (intensity files, CEL, IDAT, FASTQ) and processed results – fully transparent.

How Deep We Go – Low‑Frequency Variant Detection, Multi‑Platform Cross‑Validation, and Clinical‑Grade Interpretation

Most routine SNP genotyping labs only report calls from a single platform and rarely perform downstream interpretation. We use dual‑platform orthogonal validation (e.g., TaqMan + NGS or array + droplet digital PCR) for critical variants, achieving detection of variants at 0.5% minor allele frequency (MAF) in pooled or mosaic samples. With targeted NGS using unique molecular identifiers (UMIs), we can detect SNPs at 0.1% allele fraction – ideal for low‑prevalence somatic mutations or liquid biopsy applications. Our quantitative allele‑specific real‑time PCR (qPCR) can accurately quantify allele ratios between 1:99 to 99:1, distinguishing true heterozygosity from copy number variation or allele dropout. For complex SNP calling in challenging regions (e.g., GC‑rich, pseudogenes), we design blinded primer/probe sets and use long‑range PCR prior to NGS to avoid allele dropout. We also offer phase‑resolved SNP calling (haplotype phasing) using long‑read sequencing (PacBio HiFi) or statistical phasing when samples include family trios.

We provide clinical‑grade pharmacogenetic reports following CPIC (Clinical Pharmacogenetics Implementation Consortium) and DPWG guidelines, including actionable prescribing recommendations. For ancestry and trait prediction, we integrate third‑party algorithms (e.g., STRUCTURE, ADMIXTURE, or in‑house machine learning models) with reference populations. Our secure, HIPAA‑ and GDPR‑compliant portal allows clients to review raw data, download reports, and perform secondary analyses.

Advanced capabilities include:
- Single‑cell SNP genotyping (Fluidigm C1 or Bio‑Rad ddSEQ) – from isolated cells to resolve clonal heterogeneity.
- Copy number variation (CNV) detection from SNP array intensity data – using PennCNV or iPattern.
- Loss of heterozygosity (LOH) analysis in cancer or archived samples – from SNP array or NGS data.
- Multi‑sample QC and PCA (principal component analysis) to detect outliers, batch effects, or ancestry stratification.
- Custom SNP panel design (including insertion/deletions and multi‑allelic variants) – using our proprietary design pipeline with >98% first‑pass success.
- Conversion of SNP calls into HLA imputation (for immune system genetics) – via SNP2HLA or HIBAG.
- Integration with electronic health records (EHR) for translational research – under appropriate approvals.

We routinely achieve technical specifications: call rate >99% for typical samples (blood, buccal, saliva); reproducibility >99.9% between replicates; minor allele detection limit 0.5% (standard) or 0.1% (UMI‑NGS); concordance with reference samples >99.8%. All methods follow FDA guidance for pharmacogenetic tests, CLSI MM16 (Genotyping), and ISO 20395 for next‑generation sequencing.

Why Choose Our SNP Genotyping Services – Key Advantages

1. ISO/IEC 17025:2017 accredited and CLIA‑licensed (for clinical samples) workflows – data suitable for clinical research, diagnostic trials, and regulatory submissions.
2. Multi‑platform versatility (TaqMan, arrays, targeted NGS, ddPCR, Fluidigm) – we match the technology to your sample number, cost, and resolution needs.
3. Ultra‑sensitivity for low‑frequency and mosaic variants (down to 0.1% allele fraction) – critical for pre‑symptomatic detection, cancer monitoring, or pooled DNA screening.
4. Clinical‑grade pharmacogenetic interpretation with therapeutic recommendations – we translate raw genotypes into actionable phenotypes using CPIC/DPWG guidelines, saving you weeks of literature review.
5. Rigorous quality control and outlier detection – we flag sample swaps, contamination, or DNA degradation before sending results, preventing false findings.
6. End‑to‑end service from DNA extraction (if needed) to fully interpreted report – one submission, one data package.
7. Fast turnaround with full data transparency – 100 samples × 50 SNPs by TaqMan in 3‑4 business days; whole‑genome array (1M SNPs) for 96 samples in 5‑7 business days. You receive raw intensity data, call files, clustering plots, QC summaries, and interpreted reports.
8. Custom bioinformatics and reporting workflows – we can tailor output to your LIMS, database, or study requirements within 2‑3 weeks.
9. Competitive pricing with volume discounts – as low as $0.30 per genotype (TaqMan) or <$45 per sample for genome‑wide array (depending on sample count). Bulk projects (≥1,000 samples) receive significant discount.

We have successfully completed over 8,000 SNP genotyping projects for pharmaceutical clinical trials, academic GWAS, agricultural breeding programs, and direct‑to‑consumer genetic testing companies. Our team includes PhD geneticists, bioinformaticians, and CLIA laboratory directors.

Ready to Genotype Your SNPs?

Provide your list of SNP identifiers (rs numbers) or genomic coordinates, sample type and number, and application (research, clinical, or agriculture). We will provide a free technical consultation, a recommended platform, and a fixed‑price quote. Whether you need a single SNP for a family study or a 5‑million SNP genome‑wide scan, we deliver deep, accurate, and clinically actionable SNP genotyping tailored to your project.