Resources for Genetics Professionals — Genetic Disorders Associated with Founder Variants Common in the Gitxsan Population
Stephanie E Wallace, MD and Madelyn A Gillentine, PhD.
Author Information and AffiliationsInitial Posting: August 11, 2022.
Estimated reading time: 1 minute
A founder variant is a pathogenic variant observed at high frequency in a specific population due to the presence of the variant in a single ancestor or small number of ancestors. The presence of a founder variant can affect the approach to molecular genetic testing. When one or more founder variants account for a large percentage of all pathogenic variants found in a population, testing for the founder variant(s) may be performed first.
The table below includes common founder variants – here defined as three or fewer variants that account for >50% of the pathogenic variants identified in a single gene in individuals of a specific ancestry – in individuals of Gitxsan ancestry. Note: Pathogenic variants that are common worldwide due to a DNA sequence hot spot are not considered founder variants and thus are not included.
Table.
Genetic Disorders Associated with Founder Variants Common in the Gitxsan Population
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Included if ≤3 pathogenic variants account for ≥50% of variants identified in a specific ethnic group
AD = autosomal dominant; MOI = mode of inheritance; NA = not applicable
- 1.
This percentage does not account for the possibility of rare de novo pathogenic variants occurring in this population.
References
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