Limb disorders

Gene: BBS1

Comment on list classification: The Bardet-Biedl syndrome genes are being added back to this panel to avoid missing a potential diagnosis in the Genomic Medicine Service.

Created: 25 Nov 2019, 5:13 p.m. | Last Modified: 25 Nov 2019, 5:13 p.m.

Panel Version: 1.68

Comment on list classification: Gene made grey as it is green on the Rare multisystem ciliopathy disorders panel (v1.78) and the ciliopathy panel will be applied if a patient is suspected of having a ciliopathy, or the possibility of a ciliopathy cannot be excluded.

Created: 2 Dec 2018, 10:38 p.m.

Comment when marking as ready: Marked as read after reviewing available evidence

Created: 16 Oct 2018, 3:18 p.m.

Note: is green on the Rare multisystem ciliopathy disorders panel.

Created: 16 Oct 2018, 3:18 p.m.

Comment on mode of inheritance: Also reported as Digenic recessive in OMIM

Created: 3 Oct 2018, 3:43 p.m.

Comment on list classification: More than 3 cases/families reported of variants in this gene in individuals with Bardet-Biedl syndrome 1.

Created: 3 Oct 2018, 2:27 p.m.

In OMIM BBS1 is associated with Bardet-Biedl syndrome 1. Bardet-Biedl syndrome is an autosomal recessive and genetically heterogeneous ciliopathy characterized by retinitis pigmentosa, obesity, kidney dysfunction, polydactyly, behavioral dysfunction, and hypogonadism. BBS1 is 1 of 7 BBS proteins that form the stable core of a protein complex required for ciliogenesis.

There are several reports of individuals with variants in BBS1 who have Bardet-Biedl syndrome (PMID: 12118255; 12567324;12677556;12524598;23143442).

Beales et al (2003) (PMID: 12677556) report that analyses of 259 independent families segregating a BBS phenotype indicate that BBS1 participates in complex inheritance and that, in different families, mutations in BBS1 can interact genetically with mutations at each of the other known BBS genes, as well as at unknown loci, to cause the phenotype. They identified homozygous M390R alleles, the most frequent BBS1 mutation, in asymptomatic individuals in two families. An asymptomatic individual homozygous for p.M390R was also reported by Estrada-Cuzcano (2012) (PMID: 23143442). Other reports from Katsanis et al (2001)(PMID: 11567139) and Badano et al. (2003) (PMID: 12567324) also suggest that Bardet-Biedl syndrome is a complex interplay between multiple genetic factors.

Created: 3 Oct 2018, 2:25 p.m.