A paper may associate a gene with a disorder on the basis of one family, several unrelated cases, experimental findings or a combination of these. Those claims do not all have the same evidential strength. Before interpreting a candidate variant, researchers need to ask how firmly the gene itself is linked to the specific disease and inheritance pattern.
Separate two levels of evidence
ClinGen’s gene-disease validity framework, described by Strande and colleagues in 2017, evaluates genetic and experimental evidence supporting or contradicting a relationship. Its purpose differs from variant classification. A definitive gene-disease relationship does not make every rare variant in that gene pathogenic, while an apparently disruptive variant cannot establish a poorly supported relationship on its own. Read the foundational validity framework.
Keep the disease definition explicit. A gene can be linked to more than one disorder through different mechanisms or inheritance patterns. Evidence supporting one relationship should not be silently transferred to another simply because the gene symbol is identical.
Read the curation, not just the category
ClinGen’s classification information describes how validity categories communicate the strength of evidence. The underlying curation should be reviewed alongside its date and scope. A limited classification can reflect insufficient evidence; a disputed or refuted relationship involves a different evidential situation. Absence of a curation should not be interpreted as proof that no relationship exists. Read ClinGen’s classification information.
For a new study, distinguish additional evidence for an established relationship from evidence proposing a novel one. Replication across independent families and convincing experimental work can strengthen a claim, but repeated publication of the same individuals does not create independent evidence. Track overlap between cohorts and reports.
Design a gene-discovery argument
- Define the phenotype, inheritance model and proposed molecular mechanism.
- Show why the observed variants fit that mechanism.
- Identify alternative genetic or non-genetic explanations considered.
- Distinguish human genetic evidence from model-system support.
The clinical consequence of an uncertain association should remain explicit. A research candidate may justify further investigation without justifying a diagnostic label or altered care. Strong reporting tells readers which evidence supports the relationship, where it remains incomplete and what independent observation would most meaningfully change confidence. That makes the work more useful to both future researchers and clinical curators.