Technology before brand
Genotyping and whole-genome sequencing solve different problems.
More data is not automatically “better” for every goal. An ancestry database and a broad raw sequence are different products. Pick the technology that fits the job.
| SNP genotyping | Whole-genome sequencing | |
|---|---|---|
| What it reads | Selected known positions | Sequence reads across most of the genome |
| Typical raw export | TXT / CSV genotype file | FASTQ, BAM/CRAM, VCF depending on provider |
| Ancestry matching | Often excellent because of very large consumer databases | Varies; raw data may be richer but matching ecosystem can be smaller |
| Broad future re-analysis | Limited to sites the chip measured | Much stronger data foundation, within technical limits of the sequencing method |
| Cost | Usually lower | Usually higher |
| Medical question | If the result could change medical care, the key issue is appropriate clinical testing and interpretation, not merely choosing the largest consumer dataset. | |
Genotyping makes sense when…
- Relative matching and genealogy are the main goals.
- You want a lower-cost entry point.
- You care more about a polished consumer ecosystem than keeping maximum raw sequence data.
WGS makes sense when…
- You want a much broader raw dataset you can keep.
- You expect to revisit the data with future tools.
- You understand that broad sequencing and clinical interpretation are different things.
Avoid the false choice: WGS is not “Ancestry, but 10,000× better.” A huge relatives database can be more useful for genealogy than billions of additional sequence bases with no matching community.