NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.

Adam MP, Feldman J, Mirzaa GM, et al., editors. GeneReviews® [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2024.

Resources for Genetics Professionals — Genetic Disorders Associated with Founder Variants Common in the Navajo Population

, MD
Senior Editor, GeneReviews
Clinical Professor, Pediatrics
University of Washington
Seattle, Washington
, PhD
Molecular Genetics Editor, GeneReviews
Senior Director, Laboratory Quality Assurance
Perkin-Elmer Genomics, Inc
Pittsburgh, Pennsylvania

Initial Posting: ; Last Revision: November 3, 2022.

Estimated reading time: 2 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 Navajo 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 Navajo Population

GeneDisorderMOIDNA Nucleotide Change
(Alias 1)
Predicted Protein ChangeProportion of Pathogenic Variants in Gene 2Carrier FrequencyEthnicity (Specific Region)Reference SequencesReferences
ARSA Arylsulfatase A deficiency ARc.854+1G>A--~100% 31/25 to 1/50Navajo (Western Navajo Nation) NM_000487​.6 Pastor-Soler et al [1994], Holve et al [2001]
DCLRE1C Severe combined immunodeficiency (SCID-A)
(OMIM 602450)
ARc.597C>Ap.Tyr199Ter~100% 3~1/20 to 1/25Navajo NM_001033855​.3
NP_001029027​.1
Kwan et al [2015]
HOXA1 Navajo brain stem syndrome
(OMIM 601536)
ARc.76C>Tp.Arg26Ter~100% 31/28 4Navajo NM_005522​.5
NP_005513​.2
Holve et al [2003], Tischfield et al [2005]
MPV17 Navajo neurohepatopathy
(MPV17-related mitochondrial DNA maintenance defect)
ARc.149G>Ap.Arg50Gln~100% 31/26 4Navajo (Western Navajo Nation) NM_002437​.5
NP_002428​.1
Karadimas et al [2006], Bitting & Hanson [2016]
1/60 4Navajo (Eastern)
MYO5B Microvillus inclusion disease
(OMIM 251850)
ARc.1979C>Tp.Pro660Leu~100% 31/55 4Navajo NM_001080467​.3
NP_001073936​.1
Schlegel et al [2018]
OCA2 Oculocutaneous albinism type 2 (OMIM 203200)ARg.103171_225796del
(c.1044+1363_2080-6952; 122.5-kb del,
incl exons 10-20)
--~100% 3~1/22Navajo NG_009846​.1 Yi et al [2003]
TNFRSF11B Paget's disease
(OMIM 239000)
ARg.119932595_120030098del97504
(~100 kb del, incl entire gene)
--~100% 3UnknownNavajo NG_012202​.1 Whyte et al [2002]
USB1 Poikiloderma with neutropenia ARc.499delAp.Thr160ProfsTer98~100% 3UnknownNavajo NM_024598​.4
NP_078874​.2
Clericuzio et al [2011]

Included if ≤3 pathogenic variants account for ≥50% of variants identified in a specific ethnic group

AR = autosomal recessive; MOI = mode of inheritance

1.

Does not conform to standard HGVS nomenclature

2.

Percentage does not account for the possibility of rare de novo pathogenic variants occurring in this population.

3.

To date, additional pathogenic variants in this gene have not been reported in individuals of Navajo descent.

4.

Calculated carrier frequency based on the incidence of the disorder in individuals of Navajo ancestry; estimated carrier frequency is not based on molecular testing of the population.

Revision History

References

  • Bitting CP, Hanson JA. Navajo neurohepatopathy: a case report and literature review emphasizing clinicopathologic diagnosis. Acta Gastroenterol Belg. 2016;79:463–9. [PubMed: 28209105]
  • Clericuzio C, Harutyunyan K, Jin W, Erickson RP, Irvine AD, McLean WH, Wen Y, Bagatell R, Griffin TA, Shwayder TA, Plon SE, Wang LL. Identification of a novel C16orf57 mutation in Athabaskan patients with poikiloderma with neutropenia. Am J Med Genet A. 2011;155A:337–42. [PMC free article: PMC3069503] [PubMed: 21271650]
  • Holve S, Friedman B, Hoyme HE, Tarby TJ, Johnstone SJ, Erickson RP, Clericuzio CL, Cunniff C. Athabascan brainstem dysgenesis syndrome. Am J Med Genet A. 2003;120A:169–73. [PubMed: 12833395]
  • Holve S, Hu D, McCandless SE. Metachromatic leukodystrophy in the Navajo: fallout of the American-Indian Wars of the nineteenth century. Am J Med Genet. 2001;101:203–8. [PubMed: 11424134]
  • Karadimas CL, Vu TH, Holve SA, Chronopoulou P, Quinzii C, Johnsen SD, Kurth J, Eggers E, Palenzuela L, Tanji K, Bonilla E, De Vivo DC, DiMauro S, Hirano M. Navajo neurohepatopathy is caused by a mutation in the MPV17 gene. Am J Hum Genet. 2006;79:544–8. [PMC free article: PMC1559552] [PubMed: 16909392]
  • Kwan A, Hu D, Song M, Gomes H, Brown DR, Bourque T, Gonzalez-Espinosa D, Lin Z, Cowan MJ, Puck JM. Successful newborn screening for SCID in the Navajo Nation. Clin Immunol. 2015;158:29–34. [PMC free article: PMC4420660] [PubMed: 25762520]
  • Pastor-Soler NM, Rafi MA, Hoffman JD, Hu D, Wenger DA. Metachromatic leukodystrophy in the Navajo Indian population: a splice site mutation in intron 4 of the arylsulfatase A gene. Hum Mutat. 1994;4:199–207. [PubMed: 7833949]
  • Schlegel C, Weis VG, Knowles BC, Lapierre LA, Martin MG, Dickman P, Goldenring JR, Shub MD. Apical Membrane Alterations in Non-intestinal Organs in Microvillus Inclusion Disease. Dig Dis Sci. 2018;63:356–65. [PMC free article: PMC5797493] [PubMed: 29218485]
  • Tischfield MA, Bosley TM, Salih MA, Alorainy IA, Sener EC, Nester MJ, Oystreck DT, Chan WM, Andrews C, Erickson RP, Engle EC. Homozygous HOXA1 mutations disrupt human brainstem, inner ear, cardiovascular and cognitive development. Nat Genet. 2005;37:1035–7. [PubMed: 16155570]
  • Whyte MP, Obrecht SE, Finnegan PM, Jones JL, Podgornik MN, McAlister WH, Mumm S. Osteoprotegerin deficiency and juvenile Paget's disease. N Engl J Med. 2002;347:175–84. [PubMed: 12124406]
  • Yi Z, Garrison N, Cohen-Barak O, Karafet TM, King RA, Erickson RP, Hammer MF, Brilliant MH. A. 122.5-kilobase deletion of the P gene underlies the high prevalence of oculocutaneous albinism type 2 in the Navajo population. Am J Hum Genet. 2003;72:62–72. [PMC free article: PMC420013] [PubMed: 12469324]
Copyright © 1993-2024, University of Washington, Seattle. GeneReviews is a registered trademark of the University of Washington, Seattle. All rights reserved.

GeneReviews® chapters are owned by the University of Washington. Permission is hereby granted to reproduce, distribute, and translate copies of content materials for noncommercial research purposes only, provided that (i) credit for source (http://www.genereviews.org/) and copyright (© 1993-2024 University of Washington) are included with each copy; (ii) a link to the original material is provided whenever the material is published elsewhere on the Web; and (iii) reproducers, distributors, and/or translators comply with the GeneReviews® Copyright Notice and Usage Disclaimer. No further modifications are allowed. For clarity, excerpts of GeneReviews chapters for use in lab reports and clinic notes are a permitted use.

For more information, see the GeneReviews® Copyright Notice and Usage Disclaimer.

For questions regarding permissions or whether a specified use is allowed, contact: ude.wu@tssamda.

Bookshelf ID: NBK543113