Simpson-Golabi-Behmel Syndrome (SGBS)

Simpson-Golabi-Behmel Syndrome (SGBS) is an X-linked disorder characterized by pre- and postnatal overgrowth and distinctive facial features. Macrosomia and macrocephaly are typically noted on prenatal ultrasound or at birth and continue throughout development. The facial features are described as “coarse” and may include hypertelorism, downslanting palpebral fissures, epicanthal folds, macrostomia, macroglossia, a wide nasal bridge, ear pits or tags, and a central groove of lower lip and/or tongue. The risk for congenital anomalies is increased, including cleft lip/palate, congenital heart disease, diaphragmatic hernia, umbilical hernia, cystic hygroma, renal dysplasia, cryptorchidism, and hypospadias. Other common findings may include hypotonia, fingernail hypoplasia, interdigital webbing, polydactyly, supernumerary nipples, pectus excavatum, and skeletal anomalies. As with other overgrowth syndromes, hypoglycemia may occur in the neonatal period, and hepatomegaly has been described (Neri et al., 1998). The risk for embryonal tumors is increased but is not well established. Previous cases of Wilms tumor, hepatoblastoma, adrenal neuroblastoma, gonadoblastoma, and hepatocellular carcinoma have been published (Lapunzina 2005). Some individuals with SGBS have normal intelligence, while others exhibit mental retardation that may range from mild to severe. Even among individuals with normal intelligence, speech delay occurs frequently and may be secondary to macroglossia and malocclusion (Rodriguez-Criado et al., 2005).

Tests Available

Forms and Documents

Test Details

GPC3
  • Confirmation of a clinical diagnosis
  • Carrier testing in individuals with a known familial GPC3 mutation
  • Prenatal diagnosis in at-risk pregnancies
  • Capillary Sequencing
  • Exon Array CGH

Ordering

415E
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)

Billing

81479x1
No
Yes
  • 750.15 Macroglossia Congenital hypertrophy of tongue
  • 775.6 Neonatal hypoglycemia
  • 766.1 Other "heavy-for-dates" infants, Other fetus or infant "heavy-" or "large-for-dates" regardless of period of gestation
  • 759.89 Other Congenital malformation syndromes affecting multiple systems
  • 319 Unspecified mental retardation, Mental deficiency NOS, Mental subnormality NOS
* For price inquiries please email zebras@genedx.com

References

  1. Lin, et al., (1999) Am. J. Hum. Genet. 83:378-381
  2. Lindsay, et al., (1997) J. Med. Genet. 34:480-483
  3. Hughes-Benzie, et al., (1996) Am. J. Hum. Genet. 66:227-234
  4. Sakazume, et al., (2007) Am. J. Med. Genet. 143A: 1703-1707
  5. Li, et al., (2001) Am. J. Hum. Genet. 102:161-168
  6. Veugelers, et al., (2000) Hum. Mol. Genet. 9:1321-1328
  7. Pilia et al., (1996) Nat Genet 12:241-247
  8. Rodriguez-Criado et al., (2005) Am J Med Genet A 138A:272-277
  9. Lapunzina (2005) Am J Med Genet C 137C:53-71
  10. Neri, et al., (1998) Am. J. Hum. Genet. 79:279-283

Forms and Documents

Test Details

GPC3
  • Confirmation of a clinical diagnosis
  • Carrier testing in individuals with a known familial GPC3 mutation
  • Prenatal diagnosis in at-risk pregnancies
  • Capillary Sequencing

Ordering

415
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)|Dried Blood Spots|Buccal Brushes

Billing

81479x1
No
Yes
  • 750.15 Macroglossia Congenital hypertrophy of tongue
  • 775.6 Neonatal hypoglycemia
  • 766.1 Other "heavy-for-dates" infants, Other fetus or infant "heavy-" or "large-for-dates" regardless of period of gestation
  • 759.89 Other Congenital malformation syndromes affecting multiple systems
  • 319 Unspecified mental retardation, Mental deficiency NOS, Mental subnormality NOS
* For price inquiries please email zebras@genedx.com

References

  1. Lin, et al., (1999) Am. J. Hum. Genet. 83:378-381
  2. Lindsay, et al., (1997) J. Med. Genet. 34:480-483
  3. Hughes-Benzie, et al., (1996) Am. J. Hum. Genet. 66:227-234
  4. Sakazume, et al., (2007) Am. J. Med. Genet. 143A: 1703-1707
  5. Li, et al., (2001) Am. J. Hum. Genet. 102:161-168
  6. Veugelers, et al., (2000) Hum. Mol. Genet. 9:1321-1328
  7. Pilia et al., (1996) Nat Genet 12:241-247
  8. Rodriguez-Criado et al., (2005) Am J Med Genet A 138A:272-277
  9. Neri, et al., (1998) Am. J. Hum. Genet. 79:279-283
  10. Lapunzina (2005) Am J Med Genet C 137C:53-71

Forms and Documents

Test Details

CUL4B, EZH2, GLI3, GPC3, MED12, NFIX, NSD1, PHF6, PTCH1, PTEN, UPF3B
  • Molecular confirmation of a clinical diagnosis
  • To assist with decisions about treatment and management of individuals with macrocephaly
  • Genetic counseling
  • Diagnostic or carrier testing of at-risk relatives for specific known mutation(s) previously identified in an affected family member
  • Prenatal diagnosis for known familial mutations in at-risk pregnancies
  • Exon Array CGH
  • Next-Gen Sequencing

Ordering

699
4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL)

Billing

81321x1, 81323x1, 81401x1, 81405x1, 81406x1
No
Yes
* For price inquiries please email zebras@genedx.com