Priyanshi Patel ’22

Bardet-Biedl Syndrome (BBS) is a rare genetic condition that causes retinal degeneration, kidney failure, obesity, and cognitive impairment. BBS is a genetically heterogeneous, autosomal recessive disorder that is characterized by early-onset retinal degeneration, obesity, and cognitive impairment. In a recent investigation, scientists from the University College London and the University of Vienna were able to investigate the molecular and cellular mechanisms that underlie cognitive impairment in BBS. 

The study reveals an unknown role for BBS proteins in neuronal function. Significant structural changes were noted in the dendritic spines and dendritic length in various brain regions of Bbs mouse models. An association between neurodevelopmental and neuropsychiatric disorders with morphological and physiological changes in dendritic spines led to an inference that the dysfunction of dendritic spines may cause cognitive deficits in BBS patients. Functional loss of different Bbs proteins also affected spines to different extents, in which case some proteins only had a marginal effect on spine density, whereas others caused significant reduction in spine density. The data produced by this study supports that dendritic spine aberrations can be a vital contributing factor to cognitive deficits in BBS. 

This study may be crucial in understanding the interaction between BBS proteins and the protein in schizophrenia, and the disruption of these genes can case many psychiatric conditions. In addition, the loss of spines is prominent in many brain disorders, so probing the synaptic role of BBS proteins will contribute to a deeper understanding of the origins of these disorders. This further research shows that the loss of BBS proteins causes synaptic dysfunction in principal neurons and provides an explanation for the cognitive impairment phenotype that is observed in BBS patients. Loss of BBS proteins results in a significant reduction of dendritic spines in the main neurons of Bbs mouse models. These findings suggest that BBS proteins play a role in maintaining homeostasis in dendritic spine that may be linked to cognitive phenotype that is observed in BBS. 

References:

1. N. Haq, et. al., Loss of Bardet-Biedl syndrome proteins causes synaptic aberrations in principal neurons. PLOS Biology, Public Library of Science, 1-22 (2019). doi: 10.1371/journal.pbio.3000414.
2. Image retrieved from: https://www.gettyimages.com/detail/photo/nerve-cell-3d-biomedical-illustration-royalty-free-image/168619592?adppopup=true