Alström syndrome

Alström syndrome is a syndromic disease caused by variants in the ALMS1 gene.30,32

Though its function is still being explored, the protein encoded by ALMS1 is reported to have a role in ciliary function and structure, intracellular trafficking, and adipocyte differentiation.53

“ ‘Mom, what are you making for dinner tonight?’ He’s already starting to think about the next meal as he’s eating or finishing up the meal that he’s having. ‘What’s going to be for snack time today, Mom?’ It’s a constant.”

Christine, whose son Colton is living with Alström syndrome

Alström syndrome is inherited in an autosomal recessive manner

Inheritance

Alström syndrome is inherited in an autosomal recessive manner.30

Common features

While Alström syndrome shares many overlapping features with BBS, the presence and severity of clinical features can vary greatly across individuals.53,55

Signs and symptoms can include:33

Cone-rod-dystrophy
  • Cone-rod dystrophy
  • Photophobia
  • Nystagmus
Severe, early-onset obesity (

Severe, early-onset
obesity (<1 year old)

Hyperphagia

Hyperphagia

Short stature

Short stature

Progressive hearing loss (before age 10)

Progressive hearing
loss (before age 10)

Endocrine abnormalities, such as insulin resistance

Endocrine
abnormalities, such
as insulin resistance

Cardiomyopathy

Cardiomyopathy

Liver disease

Liver disease

Progressive kidney disease

Progressive
kidney disease

Most individuals with Alström syndrome do not survive beyond the age of 50, with the disease typically progressing to death in childhood (due to cardiac failure) or early adulthood (due to cardiac or renal failure).31

Alström syndrome can be diagnosed based on clinical features

Diagnosis

Alström syndrome can be diagnosed based on clinical features.27 Genetic testing can help provide additional evidence to support diagnosis and may help to identify family members with the same disease.52

Learn more


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