Resources for Genetics Professionals — Genetic Disorders Associated with Founder Variants Common in the Inuit Population
Stephanie E Wallace, MD and Lora JH Bean, PhD.
Author Information and AffiliationsInitial Posting: December 27, 2018; Last Revision: August 24, 2023.
Estimated reading time: 3 minutes
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 Inuit 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 Inuit Population
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Included if ≤3 pathogenic variants account for ≥50% of variants identified in a specific ethnic group
- 1.
Does not conform to standard HGVS nomenclature
- 2.
This percentage does not account for the possibility of rare de novo pathogenic variants occurring in this population.
- 3.
Additional pathogenic variants in this gene have not been reported to date in individuals of Inuit descent.
- 4.
Calculated carrier frequency is based on the incidence of the disorder in individuals of Inuit ancestry; estimated carrier frequency is not based on molecular testing of the population.
- 5.
DNA nucleotide change introduces new splice site and does not result in predicted protein change.
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Revision History
24 August 2023 (sw) Revision: updated reference sequences
24 November 2021 (sw) Revision: added Fanconi anemia
27 December 2018 (sw) Initial posting
