Common variants can shift population-level cancer associations slightly up or down. They are not diagnoses, not personal risk scores, and not screening tools.

The Biology

Most of the genetic contribution to common cancers is not carried by a single high-risk mutation. It is spread across many common variants, each of which nudges population-level association by a small amount. The variants Varia surfaces here are of this kind: typical odds ratios sit near 1.1 to 1.3 in the cohorts that reported them. An odds ratio is a simple anchor for what those numbers mean. An odds ratio of 1.2 says that, in those study populations, people with the higher-association genotype had roughly 20 percent greater odds of the diagnosis than people without it. That is a relative comparison between two groups, not a 20 percentage point jump in any one person's chance, and because the baseline risk is usually low to begin with, the real-world difference is small. Any single variant is far from deterministic.

These are population associations, not mechanisms of your own biology. They were identified by comparing large groups of people with and without a diagnosis, and they describe averages across those groups. The estimates come predominantly from European-ancestry cohorts, and Varia does not infer your ancestry from your file.

What Varia Analyzes

Twelve loci drawn from the published genome-wide literature, grouped by the cancer type their discovery studies examined:

Breast: FGFR2 rs2981582, TOX3 rs3803662, and 2q35 rs13387042.

You will not find BRCA1 or BRCA2 in this Breast group. Those are rare, high-penetrance hereditary genes that confer large lifetime risk and call for clinical genetic testing and counseling. That is a fundamentally different category from the common, low-penetrance association variants here, where each common allele shifts population-level association only slightly. Varia does not analyze BRCA1, BRCA2, or other hereditary breast cancer genes, so a clean Varia scan says nothing about your hereditary risk and is not a reason to forgo BRCA testing if your history warrants it.

Colorectal: 8q24 rs6983267, GREM1 rs4779584, and 10p14 rs10795668.

Prostate: HNF1B rs4430796 and 17q24.3 rs1859962.

Ovarian: BNC2 rs3814113.

Pancreatic: ABO rs505922 and 13q22.1 rs9543325.

Melanoma: ASIP rs910873.

Each variant is reported with its genotype, the strength of the underlying evidence, and the leading citations behind it. Where a genotype carries no copies of the associated allele, that is stated plainly rather than dressed up as a result.

How to read these findings

A higher-association genotype at one of these loci is best read as a small piece of population context, not a verdict about you. The absolute change in baseline risk attributable to any single common variant is small, the effect is not deterministic, and these variants do not act alone.

The largest contributors to cancer risk are not captured here at all: family history, age, reproductive and hormonal factors, environmental and lifestyle exposures, and the high-penetrance hereditary genes Varia excludes by design. A finding on this page is not a reason to start or skip any screening, and it does not replace conversation with a clinician or a genetic counselor.