DNA file explainers

Everything about the raw DNA file you already own — what it contains, how to handle it, what the science can and cannot say. All English explainers in one place.

All articles

• What is a raw DNA file? — Where the export lives and what it contains.
• What happens to your DNA file? — Local analysis vs upload — the privacy question.
• Build 37 vs 38 — Genome reference builds and why coordinates differ.
• Local vs cloud DNA analysis — Two architectures, different risk profiles.
• What is a SNP and an rsID? — Single-letter variants and their catalog names.
• Why DNA results differ — Chip coverage, versions and interpretation.
• What is DNA imputation? — Statistical inference vs measured genotypes.
• DNA file formats — txt, csv, zip, gz — provider export differences.
• DNA download wait times — How long each provider takes.
• Why is a SNP missing? — Chip coverage, not absence of the variant.
• DNA and genealogy — What raw files can and cannot do for family research.
• How to open a .gz DNA file — The FamilyTreeDNA trap.
• How large can a DNA file be? — Why size says nothing about quality.
• GDPR and genetic data — Special-category rights over your raw file.
• Why blonde hair darkens — Melanin, HERC2/OCA2, MC1R, KITLG.

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