Intractable Rare Dis Res. 2022;11(2):84-86. (DOI: 10.5582/irdr.2022.01024)

Diagnosing Alström syndrome in a patient followed up with syndromic obesity for years

Yakubi M, Cicek D, Demir M, Yildirim A, Hatipoglu N, Ozkul Y, Dundar M


Alström syndrome (AS) is a rare autosomal recessive monogenic disorder caused by mutations of the Alström syndrome 1 (ALMS1) gene, located on chromosome 2p13. It is a progressive multisystemic disease characterized mostly by obesity, sensorineural hearing loss, visual impairments, cardiomyopathy, insulin resistance and/or type 2 diabetes mellitus (T2DM), metabolic dysfunctions, non-alcoholic fatty liver disease, and chronic progressive kidney disease. Generally, the first clinical symptoms of the disease appear in the first years of life with a major variation of onset age. In this study, we aimed to examine the molecular diagnosis of a 6-year-old patient with suspected AS clinical symptoms. After applying clinical exome sequencing (CES) in the patient we found a homozygous deletion in exon 8 at the ALMS1 gene (c.2311_2312del). We identified a homozygous frameshift mutation. The reported variant was pathogenic according to the criteria of the American College of Medical Genetics and Genomics (ACMG). Thus, the patient was diagnosed with AS as a result of the combined clinical phenotype and genetic tests results. We hope the variant we found can expand the spectrum of ALMS1 variants in AS.

KEYWORDS: ALMS1 gene, biallelic mutations, obesity, rare diseases

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