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Explore your genetic history
An educational guide to understanding an existing DNA test and raw DNA file. Learn what common results can suggest, where their limits are, and which terms to look up.
Autosomal DNA: many family lines
Autosomal tests read selected markers across chromosomes 1–22, which come from both parents. Recombination reshuffles these segments each generation, so an autosomal file can offer information across many branches while still leaving out parts of a family story.
Mitochondrial DNA and one maternal line
Mitochondrial DNA is passed through the egg cell, so it can follow one direct maternal line: a person, their mother, and the mothers before her. This is one branch among many. It does not represent every ancestor on a person’s mother’s side.
Ancestry estimates and reference data
An ancestry estimate compares a person’s DNA patterns with selected reference samples using a statistical method. Reference groups are not equally represented, and providers may use different samples or methods. The estimate may change as those inputs change; it is not a complete family tree, a measure of cultural identity or a fixed account of history.
Variants in a raw DNA file
A raw file reports calls at selected tested positions. A variant is a difference in DNA sequence; a SNP is a variant at one nucleotide position. Neither label alone explains a trait, health outcome or ancestry. A no-call means the test did not return a usable reading at that site. A public rsID lookup can show reference records for an identifier, but it does not analyze a whole file.