Practice Test Geeks(CGL) Certified Genealogical Lecturer Practice Test
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Genetic Genealogy Flashcards

7 cards from real CGL practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

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  1. Which type of DNA test traces direct patrilineal ancestry by following the Y chromosome?

    Answer: Y-DNA test

    Y-DNA is passed from father to son with minimal change across generations, making it ideal for tracing the direct patrilineal line.

  2. What unit is used to measure the length of shared DNA segments between two individuals in genetic genealogy?

    Answer: Centimorgans (cM)

    Centimorgans (cM) measure the genetic distance of shared DNA segments and are used to estimate the relationship between two individuals.

  3. Which DNA test is most useful for finding relatives across ALL ancestral lines within approximately 5–6 generations?

    Answer: Autosomal DNA (atDNA)

    Autosomal DNA (atDNA) tests all 22 pairs of autosomes and can detect relatives from every branch of the family tree, typically within 5–6 generations.

  4. What does 'endogamy' mean in the context of genetic genealogy?

    Answer: The practice of marrying within a small community, causing elevated DNA sharing among members

    Endogamy refers to communities where people consistently marry within the same group, leading to higher-than-expected DNA sharing that can make relationship predictions less precise.

  5. What does the acronym 'IBD' stand for in genetic genealogy?

    Answer: Identical By Descent

    IBD stands for Identical By Descent, meaning the shared DNA segment was inherited from a common ancestor rather than appearing identical by chance.

  6. Which major DNA testing company uses the 'Timber' algorithm to filter out population-level false segment matches?

    Answer: AncestryDNA

    AncestryDNA uses the Timber algorithm to down-weight or remove DNA segments that are identical by descent at the population level rather than through a recent common ancestor.

  7. Within how many generations is autosomal DNA testing typically most useful for identifying genealogical relationships?

    Answer: 5–6 generations

    Due to recombination, shared autosomal DNA segments become too small to reliably detect beyond approximately 5–6 generations, limiting its practical genealogical utility.

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