Bardet-Biedl Syndrome (BBS) is a syndrome that gives rise to a spectrum of effects, encompassing visual impairments, mild obesity, extra digits, genital and kidney anomalies, and cognitive challenges.
The degeneration of retina cone cells is responsible for the vision issues. Typically, around 90% of affected individuals experience childhood-onset night blindness, progressing to peripheral vision loss and eventual blindness during adolescence. Early childhood initiates abnormal weight gain, which persists into adulthood and can lead to complications like diabetes, high blood pressure, and elevated cholesterol. Kidney irregularities span from minor functional disruptions to critical kidney failure. Developmental disabilities affect around 50% of individuals, ranging from mild learning difficulties to profound intellectual disabilities, sometimes influenced by both vision loss and the syndrome itself. Other manifestations of BBS encompass liver involvement, impaired balance and coordination, behavioral challenges, distinctive physical traits (facial and dental anomalies), and hearing impairment. Furthermore, BBS may impact the heart and reproductive system, with the specifics varying according to the BBS subtype.
BBS is caused by pathogenic (disease-causing) variants in many different genes. The test we offer covers 4 genes (BBS1, BBS2, BBS10, and BBS12), all of which exhibit autosomal recessive inheritance. This means that both parents must be carriers to have a 25% chance to have a child with the condition. BBS2 and BBS10 are more common among Ashkenazi Jews.
Resources:
Bardet-Bidel Syndrome Foundation & Family Association
Revised August 2023
