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Genotype-phenotype correlations in Bardet-Biedl syndrome
Anthony B Daniels1, Michael A Sandberg, Jianjun Chen
1Berman-Gund Laboratory for the Study of Retinal Degenerations, Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA.
Archives of Ophthalmology (Chicago, Ill. : 1960)
|March 14, 2012
Summary
Mutations in the Bardet-Biedl syndrome 1 (BBS1) gene are associated with a milder ocular phenotype compared to other BBS gene mutations. This finding aids in genetic testing and counseling for Bardet-Biedl syndrome patients.
Area of Science:
- Ophthalmology
- Genetics
- Medical Science
Background:
- Bardet-Biedl syndrome (BBS) is a rare genetic disorder characterized by a wide range of clinical manifestations.
- Ocular abnormalities are a hallmark of BBS, significantly impacting patient vision and quality of life.
Purpose of the Study:
- To investigate whether specific Bardet-Biedl syndrome (BBS) gene mutations correlate with distinct ocular phenotypes.
- To determine if BBS1 gene mutations present a different ocular presentation compared to mutations in other BBS genes.
Main Methods:
- Thirty-seven patients from 31 families meeting BBS clinical criteria with identified BBS mutations were analyzed.
- Ocular examinations and computerized full-field electroretinograms (ERGs) were performed on patients with mutations in BBS1, BBS10, and other BBS genes.
Main Results:
- Patients with BBS1 mutations exhibited significantly better visual acuity and higher ERG amplitudes compared to those with mutations in other BBS genes.
- While BBS1 patients predominantly had missense mutations, multivariate analysis indicated that mutation type (missense vs. null) did not influence visual acuity or ERG amplitude when controlling for the specific BBS gene.
- The prevalence of bone spicule pigmentation and cataracts was similar across different BBS subtypes.
Conclusions:
- Mutations in the BBS1 gene are associated with a milder ocular phenotype in Bardet-Biedl syndrome patients.
- These genotype-phenotype correlations can inform genetic testing strategies and genetic counseling for individuals with BBS.
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