Bardet-Biedl syndrome (BBS) is a heterogeneous disease caused by abnormal cilia. Mutations in at least 18 genes result in different types of BBS. The most common symptoms of BBS are retinitis pigmentosa progressing to blindness, obesity, polydactyly, hypogonadism, and learning disabilities. BBS is usually inherited in an autosomal recessive manner. Mutations in the BBS2 gene account for approximately 8% of all BBS cases and are the third most frequent cause of BBS. Two BBS2 variants, p.D104A and p.R632P, are reported to be founder mutations in the Ashkenazi Jewish populations. Testing for these two mutations is expected to identify more than 95% of carriers in the Ashkenazi Jewish population, where the carrier frequency is approximately 1 in 140.
Full gene sequencing is available for reproductive partners of known mutation carriers. Prenatal diagnosis is also available. Prior to ordering prenatal testing, please contact our laboratory at 212-241-7518 to discuss.
1. Fedick A, Jalas C, Abeliovich D, Krakinovsky Y, Ekstein J, Ekstein A, Treff NR. Carrier frequency of two BBS2 mutations in the Ashkenazi population. Clin Genet. 2014 Jun85(6):578-82.
Two 5-10 ml tubes of anticoagulated blood in EDTA (lavender top) or two 5-10 ml tubes of anticoagulated blood in ACD (yellow top).
Amniotic Fluid: 10 ml in conical tube
Cultured Cells: Two confluent T-25 flasks
Additionally, please send:
5-10 ml paternal blood in EDTA (lavender top) in case paternal confirmation studies are necessary
Forms and Brochures
Carrier Screening Requisition and Consent[PDF]
Expanded Ashkenazi Jewish Carrier Screening Brochure[PDF]
Ashkenazi Jewish Carrier Screening Panel