Identification of a variant in the USH1G gene in a family with Usher syndrome

Nancy Gélvez, Greizy López, Marta L. Tamayo, .

Keywords: Usher syndromes, genetics, retinitis pigmentosa, hearing loss, sensorineural, DNA mutational analysis, Colombia

Abstract

Usher syndrome is characterized by congenital sensorineural hearing loss, retinitis pigmentosa, and vestibular dysfunction. It is the most common cause of deafblindness worldwide. It is classified into three clinical types and twelve genetic subtypes.
We report a case of a family affected by Usher syndrome due to a variant in the USH1G gene, coding for the SANS protein. The ocular and auditory tests were performed for clinical confirmation of the diagnosis. The molecular study consisted of a next-generation sequencing panel containing 14 genes associated with Usher syndrome: MYO7A, USHC1, CDH23, PCDH15, USHG1, CIB2, USH2A, ADGRV1, WHRN, CLRN1, HARS, PDZD7, CEP250, C2orf71.
We present the case of a 13-year-old girl from a consanguineous Colombian family diagnosed with Usher syndrome type 1G. Clinical evaluations confirmed auditory, vestibular, and ocular alterations. Molecular analysis identified the homozygous p.Glu171Ter variant in the USH1G gene.
We highlight the importance of an early diagnosis of Usher syndrome. Although the variant frequency in the USH1G gene is low, it should not be underestimated; the exact etiology must be identified in these families. We recommend establishing a panel with Colombianspecific variants to perform more accurate Usher syndrome diagnoses, and in the future, to guide the development of gene therapies.

Downloads

Download data is not yet available.

References

Tamayo M, Bernal JE, Tamayo GE, Frías JL. Study of the etiology of deafness in an institutionalized population in Colombia. Am J Med Genet.1992;44:405-8. https://doi.org/10.1002/ajmg.1320440403

Tamayo ML, Bernal JE, Tamayo GE, Frías JL, Alvira G, Vergara O, et al. Usher syndrome: Results of a screening program in Colombia. Clin Genet. 1991;40:304-11. https://doi.org/10.1111/j.1399-0004.1991.tb03100.x

Hope CI, Bundey S, Proops D, Fielder AR. Usher syndrome in the city of Birmingham--prevalence and clinical classification. Br J Ophthalmol. 1997;81:46-53. https://doi.org/10.1136/bjo.81.1.46

Spandau UH, Rohrschneider K. Prevalence and geographical distribution of Usher syndrome in Germany. Graefes Arch Clin Exp Ophthalmol. 2002;240:495-8. https://doi.org/10.1007/s00417-002-0485-8

Keats BJ, Corey DP. The Usher syndromes. Am J Med Genet. 1999;89:158-66. https://doi.org/10.1002/(SICI)1096-8628(19990924)89:3<158::AIDAJMG6>3.0.CO;2-%23

Yoshimura H, Miyagawa M, Kumakawa K, Nishio SY, Usami S. Frequency of Usher syndrome type 1 in deaf children by massively parallel DNA sequencing. J Hum Genet. 2016;61:419-22. https://doi.org/10.1038/jhg.2015.168

Yan D, Liu XZ. Genetics and pathological mechanisms of Usher syndrome. J Hum Genet. 2010;55:327-35. https://doi.org/10.1038/jhg.2010.29

Hope CI, Bundey S, Proops D, Fielder AR. Usher syndrome in the city of Birmingham--prevalence and clinical classification. Br J Ophthalmol. 1997;81:46-53. https://doi.org/10.1136/bjo.81.1.46

Rosenberg T, Haim M, Hauch AM, Parving A. The prevalence of Usher syndrome and other retinal dystrophy-hearing impairment associations. Clin Genet. 1997;51:314-21. https://doi.org/10.1111/j.1399-0004.1997.tb02480.x

Weil D, El-Amraoui A, Masmoudi S, Mustapha M, Kikkawa Y, Laine S, et al. Usher síndrome type I G (USH1G) is caused by mutations in the gene encoding SANS, a protein that associates with the USH1C protein, harmonin. Hum Mol Genet. 2003;12:463-71. https://doi.org/10.1093/hmg/ddg051

Jaijo T, Aller E, García-García G, Aparisi MJ, Bernal S, Ávila-Fernández A, et al. Microarraybased mutation analysis of 183 Spanish families with Usher syndrome. Invest Ophthalmol Vis Sci. 2010;51:1311-7. https://doi.org/10.1167/iovs.09-4085

Mustapha M, Chouery E, Torchard-Pagnez D, Nouaille S, Khrais A, Sayegh FN, et al. A novel locus for Usher syndrome type I, USH1G, maps to chromosome 17q24-25. Hum Genet. 2002;110:348-50. https://doi.org/10.1007/s00439-002-0690-x

Ouyang XM, Yan D, Du LL, Hejtmancik JF, Jacobson SG, Nance WE, et al. Characterization of Usher syndrome type I gene mutations in an Usher syndrome patient population. Hum Genet. 2005;116:292-9. https://doi.org/10.1007/s00439-004-1227-2

Kikkawa Y, Shitara H, Wakana S, Kohara Y, Takada T, Okamoto M, et al. Mutations in a new scaffold protein SANS cause deafness in Jackson shaker mice. Hum Mol Genet. 2003;12:453-61. https://doi.org/10.1093/hmg/ddg042

Kalay E, de Brouwer AP, Caylan R, Nabuurs SB, Wollnik B, Karaguzel A, et al. A novel D458V mutation in the SANS PDZ binding motif causes atypical Usher syndrome. J Mol Med. 2005;83:1025-32. https://doi.org/10.1007/s00109-005-0719-4

Kimberling WJ, Moller C. Clinical and molecular genetics of Usher syndrome. J Am Acad Audiol. 1995;6:63-72. https://doi.org/10.1111/j.1399-0004.1991.tb03100.x

Kimberling WJ, Hildebrand MS, Shearer AE, Jensen ML, Halder JA, Trzupek K, et al. Frequency of Usher syndrome in two pediatric populations: Implications for genetic screening of deaf and hard of hearing children. Genet Med. 2010;12:512-6. https://doi.org/10.1097/GIM.0b013e3181e5afb8

Fortnum HM, Summerfield AQ, Marshall DH, Davis AC, Bamford JM. Prevalence of permanent childhood hearing impairment in the United Kingdom and implications for universal neonatal hearing screening: Questionnaire based ascertainment study. BMJ 2001;323:536-40. https://doi.org/10.1136/bmj.323.7312.536

Bashir R, Fatima A, Naz S. A frameshift mutation in SANS results in atypical Usher syndrome. Clin Genet. 2010;78:601-3. https://doi.org/10.1111/j.1399-0004.2010.01500.x

How to Cite
1.
Gélvez N, López G, Tamayo ML. Identification of a variant in the USH1G gene in a family with Usher syndrome. Biomed. [Internet]. 2025 Sep. 22 [cited 2026 Jan. 13];45(4):528-34. Available from: https://revistabiomedicaorg.biteca.online/index.php/biomedica/article/view/7498

Some similar items:

Published
2025-09-22
Section
Case presentation

Altmetric

Article metrics
Abstract views
Galley vies
PDF Views
HTML views
Other views
Crossref Cited-by logo
Escanea para compartir
QR Code