Test Directory

Test Code
2306
Test Name
Simpson-Golabi-Behmel Syndrome, Type 2
CPT Codes
81479
Expected Turnaround Time
Typically 2 to 4 weeks from receipt of a sample in the laboratory. All cases involving ongoing pregnancies will be expedited.
Clinical Utility
Genetic analysis to provide a molecular diagnosis of this disorder. Recommended for individuals with a personal and/or family history of this disorder to ensure appropriate treatment and establish recurrence risk for family members.
Specimen and Container Info

Non-Prenatal Specimens

Preferred/Alternate

Specimen Type

Containers

Volume

Preferred Specimen Type

Whole Blood

Lavender Top (EDTA)

3 mL

Alternate Specimen Type

Genomic DNA

1.5 mL Tube

3 µg (at a concentration of at least 30 ng/µl), preferably in TE solution.

Alternate Specimen Type

Fibroblasts

T-25 Flasks

2 confluent T-25 flasks, filled to capacity

Alternate Specimen Type

Saliva (Whole blood is recommended for CNV)

DNA Self-Collection Kit or Oragene Saliva Collection Kit for Young Children

Follow kit instructions (www.dnagenotek.com)

Prenatal Specimens

Either specimen type below is acceptable.

Specimen Type

Containers

Volume

Cultured cells

T-25 Flasks

2 confluent T-25 flasks derived from amnio or CVS samples.

Genomic DNA

1.5 mL Tube

3 µg (at a concentration of at least 30 ng/µl), preferably in TE solution.

NOTE: For specimens from outside of North America, the preferred specimen type is Genomic DNA. HNL Genomics does not recommend shipping whole blood or cultured cells from any location other than the United States, Canada, or Mexico.

Transport Instructions
  • Transport at room temperature within 24 hours.
  • If the specimen cannot be transported to the lab within 24 hours, refrigerate for up to 72 hours.
  • Do not freeze or expose to extreme temperatures, refrigerate for up to 72 hours if cannot be transported to lab within 24 hours. 
Stability Requirements

Room Temperature

24 hours

Refrigerated

72 hours

Causes for Rejection
  • Improperly labeled specimen (minimum of two patient identifiers)
  • Inappropriate specimen type
  • Incomplete or incorrect test request form
  • Insufficient volume
  • Specimen has leaked in transit
  • Specimen without a test order
Methodology
Next Generation Sequencing and Copy Number Variation Analysis
Performing Location
Genomics - Snowdrift
Alternate Names
SGBS2
Description

Overgrowth syndromes are characterized by pre- and postnatal overgrowth, accelerated osseous maturation, a characteristic craniofacial appearance, and developmental delay. All of these syndromes show considerable phenotypic overlap; however, these disorders also have some distinct clinical features.  Congenital heart anomalies, scoliosis, renal abnormalities and seizures are common in Sotos syndrome, while Weaver syndrome is associated with campodactyly, umbilical hernia, a hoarse cry in infancy, and soft, doughy skin. Cohen-Gibson syndrome is clinically related to Weaver syndrome. Simpson-Golabi-Behmel syndrome, type 1 can be distinguished from other overgrowth disorders by its unique set of features, including coarse facies, macrostomia, macroglossia, cleft palate, postaxial polydactyly, rib abnormalities, and congenital heart defects. Simpson-Golabi-Behmel syndrome, type 2 clinically overlaps with Simpson-Golabi-Behmel syndrome, type 1. Simpson-Golabi-Behmel syndrome, type 2 is more severe and often lethal in infancy. Patients with multiple congenital anomalies-hypotonia-seizures syndrome 2  have multiple congenital anomalies, neonatal hypotonia and myoclonic seizures. Kosaki overgrowth syndrome is associated with hyperelastic skin, premature aging and neurodegeneration. In addition to skeletal overgrowth Marfan syndrome is characterized by ocular and cardiovascular features. Additional clinical features in Luscan-Lumish syndrome include macrocephaly, behavioral problems and seizures.

Gene Disorder MIM Inheritance
DNMT3A Tatton-Brown-Rahman syndrome (TBRS) 615879 AD
EED Cohen-Gibson syndrome (COGIS) 617561 AD
EZH2 Weaver syndrome (WVS) 277590 AD
FBN1 Marfan syndrome (MFS) 154700 AD
GPC3 Simpson-Golabi-Behmel syndrome, type 1 (SGBS1) 312870 XLR
NFIX Marshall-Smith syndrome (MRSHSS)
Sotos syndrome 2 (SOTOS2)
602535
614753
AD
AD
NSD1 Sotos syndrome 1 (SOTOS1) 117550 AD
OFD1 Simpson-Golabi-Behmel syndrome, type 2 (SGBS2) 300209 XLR
PDGFRB Kosaki overgrowth syndrome (KOGS) 616592 AD
PIGA Multiple congenital anomalies-hypotonia-seizures 
           syndrome 2 (MCAHS2)
300868 XLR
SETD2 Luscan-Lumish syndrome (LLS) 616831 AD
Testing Schedule
Monday-Friday
Genes
OFD1
MIM
300209
Disease Group
Craniosynostosis and Craniofacial Disorders, Dysmorphology, Neuromuscular, Skeletal Disorders