Bardet-Biedl Syndrome

Test Description:

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.

Specimen Requirements


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).


Chorionic Villi: 5-10 mg in conical tube with sterile saline OR transport media
Amniotic Fluid: 10 ml in conical tube
Cultured Cells: Two confluent T-25 flasks

Additionally, please send:

5-10 ml maternal blood in EDTA (lavender top) required to perform MCC studies on all prenatal samples and in case maternal confirmation studies are necessary
5-10 ml paternal blood in EDTA (lavender top) in case paternal confirmation studies are necessary

Ordering Information


Ship at room temperature

Turnaround Time:

10 – 14 days

CPT Codes:


Forms and Brochures

Carrier Screening Requisition and Consent[PDF]
Expanded Ashkenazi Jewish Carrier Screening Brochure[PDF]
Ashkenazi Jewish Carrier Screening Panel