This guide explains each part of an education card: the cited source, what the research examined, where uncertainty remains, and questions you may want to raise with a healthcare professional.
Researchers use different measures depending on whether a variant follows a Mendelian pattern or contributes a smaller effect alongside many other factors. Cards show the available measure for each variant.
Used for Mendelian variants
Of people with this genotype, what proportion was reported with the condition during the study period?
Range: 0% – 100%
Example: Published estimates for HFE C282Y homozygotes vary by population and study design.
Used for complex or polygenic research findings
How do the reported odds compare between groups with and without the variant?
Range: 0 – ∞ (1.0 = no effect)
Example: An odds ratio compares study groups. It does not state an individual's probability or relative risk.
Uses the same effect measure as the odds ratio, shown on a symmetric scale
The log of the odds ratio. Cards may show it as an effect-size measure on a symmetric scale, where equal values in opposite directions have equal magnitude.
Range: −∞ to +∞ (0 = no effect)
Example: log₂(2) = +1; log₂(0.5) = −1. Both represent the same magnitude in opposite directions.
| Mendelian (single-gene) | Complex (polygenic) | |
|---|---|---|
| Caused by | ONE gene with a large reported effect | MANY genes, often hundreds, plus environmental factors |
| Inheritance | May follow dominant, recessive, X-linked, or mitochondrial inheritance patterns | No single inheritance pattern; the estimate combines multiple small effects |
| Number of variants | 1–few rare, high-impact | Hundreds, each tiny effect |
| Card archetype | mendelian - penetrance bar | complex_trait - log₂(OR) bar |
| Examples | Examples vary by condition and evidence source | APOE/Alzheimer's, TCF7L2/T2D, FTO/obesity |
Use a log₂(OR) bar centred at 0. Negative values left of center, positive values right. Equal-strength variants are equidistant from center.
Use a 0 to 100% bar for the proportion reported in a study for a given genotype. It may include inheritance-pattern and population-frequency context.
Each card includes an evidence tier based on independent replications and the cited source material.
| Tier | Stars | Meaning |
|---|---|---|
| STRONG | ★★★★★ | Genome-wide significance reported in large meta-analyses or a well-established Mendelian finding. |
| VALIDATED | ★★★★ | Three or more independent GWAS replications. |
| MODERATE | ★★★ | 1–2 replications with some heterogeneity across studies. |
| EMERGING | ★★ | Single large study, awaiting independent replication. |
| EXPLORATORY | ★ | Candidate-gene-era finding with weak modern replication. Treat with caution. |
| Code | Pattern | What it means |
|---|---|---|
| AD | Autosomal dominant | A variant in one copy may be sufficient for a trait to be inherited. Each child of an affected parent can have a 50% chance of inheriting it. |
| AR | Autosomal recessive | Two copies may be needed for the trait. If both parents have one copy, each child can have a 25% chance of inheriting two copies. |
| XLR | X-linked recessive | X-linked inheritance can affect people differently depending on their sex chromosomes. A parent with one relevant X-linked copy may pass it to half of their children. |
| XLD | X-linked dominant | In X-linked inheritance, an affected father passes the relevant X chromosome to all daughters. |
| MT | Mitochondrial | Mitochondrial DNA is inherited from the mother. Children may inherit the relevant variant from an affected mother, but not from an affected father. |
On complex-trait cards, the bar is centred at 0 (the no-effect point). The triangular marker sits at log₂(OR), so:
Colour reflects direction relative to the reference point. Cards list the original odds ratio and a plain-language comparison alongside the log₂ value.
The cards shown here are examples. Available content depends on the source data and information provided for the site.
These cards are for education only.
Genetic findings vary with environment, lifestyle, other variants, and study design. Do not use these cards to make health decisions. Discuss personal questions with a qualified professional. Lower-tier findings require greater caution.
