Topic
SNPs Explained
A single-nucleotide polymorphism (SNP) is a variation at one position in your DNA. Most are common, most have small effects, and only a handful change a real-world decision. These articles cover the SNPs that do — the ones in your raw 23andMe / AncestryDNA / MyHeritage file that meaningfully inform medication choice, supplement strategy, lifestyle adjustments, or clinical screening conversations.
25 articles
clinical genetics
Penetrance vs Expressivity: The Difference
Learn how genetic penetrance differs from variable expressivity, why both depend on context, and what a consumer raw DNA file cannot tell you alone.
October 20, 2026 · 4 min read
snps explained
SNP Microarray: What Raw DNA Files Measure
Learn how SNP microarrays create selected marker calls, what appears in a raw DNA file, and why those rows are not a full clinical genome result.
October 13, 2026 · 5 min read
population frequency
Allele Frequency: How Common a DNA Variant Is
Learn what allele frequency means in raw DNA reports, why population context matters, and how to avoid treating frequency as a personal diagnosis.
October 12, 2026 · 5 min read
clinical genetics
Genetic Penetrance: What a DNA Variant Can Mean
Learn what genetic penetrance means, why a variant may not lead to a trait, and how to review raw DNA findings without overreading them.
October 10, 2026 · 5 min read
raw dna
Genetic Variants: What Raw DNA Files Can Show
Learn what genetic variants are, how they appear in raw DNA files, and why a marker, genotype, and clinical interpretation are separate things.
October 9, 2026 · 5 min read
snps explained
Homozygous vs Heterozygous Genotypes in Raw DNA
Compare homozygous and heterozygous genotype calls in raw DNA data, with examples, limits, and the context needed before interpreting a marker.
October 3, 2026 · 5 min read
methylation
DNA Methylation Genes: What Raw DNA Can Show
Learn which methylation-related genes may appear in a consumer raw DNA file, what those variants can and cannot tell you, and when lab testing matters.
October 2, 2026 · 7 min read
snps explained
Heterozygous Genotype: Reading Two Different Alleles
Learn what a heterozygous genotype means in a raw DNA row, how it differs from homozygous, and why the label alone does not establish a health finding.
September 24, 2026 · 4 min read
snps explained
Genotyping vs Sequencing: What Your DNA File Contains
Compare array genotyping and DNA sequencing by coverage, output and limitations, then check what an existing raw DNA file can actually support.
September 22, 2026 · 4 min read
snps explained
DNA Strand Orientation: Why Genotype Letters Can Differ
Understand plus and minus strands, complementary allele letters, and the reference checks needed before deciding that two raw DNA results disagree.
September 18, 2026 · 4 min read
snps explained
rsID Meaning: How to Read the Labels in Raw DNA Data
Learn what an rsID identifies, how it differs from your genotype, and which reference details to check before interpreting a marker in raw DNA data.
September 15, 2026 · 4 min read
snps explained
GRCh37 vs GRCh38: Comparing Locations in Raw DNA Data
Learn why DNA coordinates differ between GRCh37 and GRCh38, how to check a raw file's build, and when a position mismatch needs technical review.
September 13, 2026 · 5 min read