Unraveling Alström syndrome: Homozygous mutation c.2729C>G in ALMS1 gene across an extended family

Mol Genet Genomic Med. 2024 Jan;12(1):e2314. doi: 10.1002/mgg3.2314. Epub 2023 Nov 8.

Abstract

Background: Alström syndrome (AS) represents an exceptionally rare genetic disorder characterized by a constellation of features including cardiomyopathy, progressive hearing and vision impairment, as well as obesity. This study seeks to elucidate the genetic underpinnings of this syndrome within the Saudi Arabian population.

Methods: Employing an extended family cohort, we conducted an exhaustive molecular genetic assessment to delineate the presence of Alström syndrome. Additionally, we conducted an extensive review of existing literature from Saudi population to contextualize our findings within the broader understanding of the disorder in our country.

Results: Within our studied extended family, we identified two individuals harboring the homozygous pathogenic mutation (c.2729C>G) in the ALMS1 gene [NM_015120.4:c.2729C>G (p.Ser910*)]. Notably, carrier status was observed in the parents, whereas some siblings exhibited typical alleles while others were carriers of the mutation. Intriguingly, a review of the literature unveiled six distinct reports documenting a total of 20 Alström syndrome patients within the Saudi Arabian population, each presenting with distinct novel mutations.

Conclusions: In cases featuring cardiomyopathy, obesity, and progressive hearing and vision loss, Alström syndrome merits inclusion within the differential diagnosis. To confirm the diagnosis, molecular genetic assessment of the ALMS1 gene is imperative, offering definitive clarity amidst the complex clinical presentation. This investigation reinforces the importance of genetic scrutiny for precise diagnosis and highlights the unique genetic landscape of Alström syndrome within the Saudi Arabian population.

Keywords: ALMS1 gene; Alstrom syndrome.

Publication types

  • Review

MeSH terms

  • Alstrom Syndrome* / diagnosis
  • Alstrom Syndrome* / genetics
  • Cardiomyopathies*
  • Cell Cycle Proteins / genetics
  • Extended Family
  • Humans
  • Mutation
  • Obesity
  • Saudi Arabia

Substances

  • Cell Cycle Proteins
  • ALMS1 protein, human