Roberts Syndrome (RBS) is an autosomal recessive disorder characterized by pre- and postnatal growth retardation, microcephaly, bilateral cleft lip and palate, and mesomelic symmetric limb reduction. Mental retardation is reported in the majority of affected individuals and mortality is high among severely affected fetuses and newborns. RBS is a chromosome cohesinopathy, and diagnosis typically relies upon cytogenetic testing in peripheral blood of individuals with suggestive clinical findings. However, bi-allelic mutations in the gene ESCO2 recently have been identified in all RBS patients tested. A number of different mutations in ESCO2 have been reported in these families. Exons 2 through 11 of ESCO2 are PCR amplified and subjected to bi-directional sequencing. All nucleotide variations suspected to be pathogenic for RBS are confirmed on a re-extracted DNA sample. Molecular testing of RBS is used for confirmation of a clinical diagnosis, carrier testing of individuals with a family history of the disorder and prenatal diagnosis.
1. Vega, H, Waisfisz, Q, Gordillo, M, Sakai, N, Yanagihara, I, Yamada, M, van Gosliga, D, Kayserili, H, Xu, C, Ozono, K, Jabs, EW, Inui, K, Joenje, H, Roberts syndrome is caused by mutations in ESCO2, a human homolog of yeast ECO1 that is essential for the establishment of sister chromatid cohesion. Nat Genet. 2005 May;37(5):468-70.
2. Schüle, B, Oviedo, A, Johnston, K, Pai, S, Francke, U. Inactivating mutations in ESCO2 cause SC phocomelia and Roberts syndrome: no phenotype-genotype correlation. Am J Hum Genet. 2005 Dec;77(6):1117-28.
Two 5-10 ml tubes of anticoagulated blood. The preferred anticoagulant is EDTA (lavendar top tubes), ACD (yellow top) tubes are also accepted.
Two confluent T-12.5 flasks or more than 2 mg of direct CVS tissue are required for prenatal samples.
Shipping: Send at room temperature.
Turnaround Time: 3-4 weeks
CPT Codes: 83891, 83898x12, 83904x12, 83912
Requisition Form: General Test Requisition [PDF]
Additional Information: Roberts Syndrome Infosheet [PDF]
Prior to ordering prenatal testing, please contact our laboratory at 212-241-7518 to discuss.