Clinical variability of BBS1 across siblings.

Bardet-Biedl syndrome (BBS), an autosomal recessive ciliopathy with pleiotropic effects, manifests as a spectrum of anomalies involving multiple genes and affects fewer than 3,000 individuals in the USA. Due to its rarity and phenotypic variability, early diagnosis of BBS poses a significant challenge. Therefore, we aim to shed light on the intrafamilial phenotypic variation of BBS resulting from a BBS1 variant by delineating the clinical presentation in two siblings.