Prenatal Cytogenetics/Molecular Cytogenetics & Biochemical Testing

GeneDx offers full-service molecular cytogenetic testing, including a custom-designed targeted prenatal array CGH test.  The prenatal array will rule out 100 clinically defined genomic disorders as well as terminal, subtelomeric and pericentromeric chromosomal rearrangements.  Supplemeting these tests are: FISH that can be requested as a stand-alone test for genomic disorders or specific segmental aneuploidies, or as a follow-up test for parents of a proband with a positive array CGH result; chromosome analysis and amniotic fluid alpha-fetoprotein (AF-AFP) with reflex to acetylcholinesterase (AchE) if AF-AFP is elevated.

Due to the time-sensitive nature of prenatal diagnosis, each sample receives case-management by a genetic counselor.  All tests requested for on-going pregnancies are given the highest priority in the lab and are performed on a RUSH basis.  Therefore, the turnaround time will be faster than for non-prenatal cases.  Please contact a genetic counselor at 301-519-2100 or prenatal@genedx.com prior to sending a prenatal sample.

CLICK HERE TO SEE REQUIREMENTS FOR PRENATAL SPECIMENS.

 

Test Available	Fetal Indication	More Information
Chromosome Analysis Amniotic Fluid Chorionic Villi Cultured amniotic fluid or CVS  PUBS	Advanced maternal age Abnormal ultrasound findings Suspected deletion/duplication syndrome Family history of known or suspected chromosome imbalances	Test Information sheet  Prenatal Sample Submission Form  Billing information
Rapid Aneuploidy FISH Amniotic Fluid Chorionic Villi Cultured amniotic fluid or CVS  PUBS	Advanced maternal age Abnormal ultrasound findings	Test Information sheet  Prenatal Sample Submission Form  Billing information
Prenatal targeted array CGH: custom-designed 60K oligonucleotide array CGH targeting 100 common or novel microdeletionand microduplication syndromes, any other genomic imbalances greater than 1.5 Mb, and uniparental disomy of chromosomes 6, 7, 11, 14, 15, and 20. Amniotic Fluid Chorionic Villi Cultured amniotic fluid or CVS	Advanced maternal age Abnormal ultrasound findings Suspected deletion/duplication syndrome Family history of known or suspected chromosome imbalances	Test Information sheet Array loci list  Prenatal Sample Submission Form Clinical information form (please submit with test requisition)    Billing information
Amniotic Fluid Alpha-fetoprotein (AF-AFP) and Acetylcholinesterase (AChE) Amniotic Fluid	Abnormal ultrasound findings, including open neural tube defects and ventral wall defects Abnormal maternal serum screening results	Test Information sheet  Prenatal Sample Submission Form     Billing information
FISH analysis for Velocardiofacial Syndrome and DiGeorge Syndrome Amniotic Fluid Chorionic Villi Cultured amniotic fluid or CVS	Abnormal ultrasound findings Prenatal diagnosis in at-risk pregnancies Family history of known or suspected VCFS Confirmation of a clinical diagnosis	Test Information sheet  Prenatal Sample Submission Form  Billing information
Zygosity Testing Amniotic Fluid Chorionic Villi Cultured amniotic fluid or CVS	Multiple pregnancies	Test Information sheet  Prenatal Sample Submission Form  Billing information
Whole Genome Array CGH for Products of Conception: custom-designed 180K oligonucleotide array CGH for detection of copy number variants anywhere in the unique sequence of the genome. Includes targeted exon-level coverage of 75 genes associated with neurodevelopmental disorders and 66,000 SNP probes throughout the genome to detect stretches of homozygosity extending 10 Mb or longer.	Abnormal ultrasound findings Ambiguous chromosome analysis results Suspected deletion/duplication syndrome Miscarriage Fetal demise	Test Information sheet  Prenatal Sample Submission Form    Billing information

GeneDx prenatal diagnostic services include full gene sequencing for a limited number of genetic disorders, a comprehensive prenatal Noonan syndrome panel, as well as a custom-designed prenatal targeted array CGH. For more information for each test, see the printable information sheet below or under the Gene or Disorder on our menu of Diagnostic Tests.

Due to the time-sensitive nature of prenatal diagnosis, each sample receives case-management by a genetic counselor. All tests requested for on-going pregnancies are given the highest priority in the lab and are performed on a RUSH basis. Therefore, the turnaround time will be faster than for non-prenatal cases, but nevertheless may be several weeks. 

CLICK HERE TO SEE REQUIREMENTS FOR PRENATAL SPECIMENS.
 

Genetic Disorder	Fetal Ultrasound Indication	Test Available	More Information
100 common or novel microdeletion and microduplication syndromes   See array loci list for list of diseases/loci targeted on our prenatal array CGH	•Abnormal ultrasound findings •Ambiguous chromosome analysis results •Suspected deletion/duplication syndrome •Family history of known or suspected chromosome imbalances	Prenatal targeted array CGH: custom-designed 60K oligonucleotide array CGH targeting 100 common or novel microdeletion and microduplication syndromes and any other genomic imbalances greater than 1.5 Mb and that are of potential clinical significance.	Test Information sheet Array loci list  Prenatal Sample Submission Form  Billing information
Noonan syndrome	•Cystic hygroma •Increased nuchal translucency •Cardiac defects •Lymphedema •Macrosomia •Polyhydramnios	Comprehensive Prenatal Noonan Syndrome Panel - GeneDx custom-designed resequencing array including 8 genes known to cause Noonan syndrome or related disorders (BRAF, HRAS, KRAS, MAP2K1, MAP2K2, PTPN11, RAF1, and SOS1) and mutation specific analysis for the Ser2Gly SHOC2 gene mutation using bi-directional DNA sequencing.	Test Information sheet  Prenatal Sample Submission Form  Billing information
Holoprosencephaly	•Holoprosencephaly •Cleft lip/palate •Hydrocephalus	TGIF, SHH, SIX3, and ZIC2 genes •Full gene sequencing •Deletion/duplication testing	Test Information sheet  Prenatal Sample Submission Form   Billing information
X-linked hydrocephalus / MASA syndrome / CRASH syndrome	Hydrocephalus and/or Aqueductal stenosis	L1CAM gene (L1-cell adhesion molecule) •Full gene sequencing For female fetus only: Deletion/duplication testing	Test Information sheet  Prenatal Sample Submission Form   Billing information
Townes-Brocks syndrome	Fetal renal malformations accompanied by characteristic abnormalities of the limbs and extremities	SALL1 gene •Full gene sequencing	Test Information sheet  Prenatal Sample Submission Form  Billing information
Duane-Radial-Ray syndrome / Acro-renal-ocular syndrome	Fetal renal malformations accompanied by characteristic abnormalities of the limbs and extremities	SALL4 gene •Full gene sequencing •Deletion/duplication testing	Test Information sheet  Prenatal Sample Submission Form  Billing information
Holt-Oram syndrome	Characteristic upper-limb malformations and/or fetal heart defects	TBX5 gene •Full gene sequencing	Test Information sheet  Prenatal Sample Submission Form  Billing information
CHARGE syndrome	•Fetal heart defects •CNS malformations •Cleft lip/palate •Renal and gastrointestinal abnormalities	CHD7 gene •Full gene sequencing	Test Information sheet  Prenatal Sample Submission Form  Billing information
Ectrodactyly-Ectodermal Dysplasia-Cleft Lip/Palate (EEC) / Split Hand-Split Foot Malformation (SHFM) / Hay-Wells syndrome	Fetal limb and extremity abnormalities	TP73L (TP63,p63) gene •Sequencing of select exons (hotspots)	Test Information sheet  Prenatal Sample Submission Form   Billing information
Smith-Lemli-Opitz syndrome	•Intrauterine growth retardation (IUGR) •Major brain, heart, limb or renal malformations •Ambiguous genitalia, with female genitalia or severe hypospadias, seen in a XY fetus	DHCR7 gene •Full gene sequencing •Deletion/duplication testing is performed if sequencing idenifies a mutation in only one allele of the DHCR7 gene **Prenatal measurement of 7-DHC levels is recommended prior to genetic testing**	Test Information sheet  Prenatal Sample Submission Form   Billing information
Androgen Insensitivity syndrome (AIS)	Fetal karyotype is 46,XY but ultrasound reveals apparently female or ambiguous genitalia.	AR gene •Full gene sequencing	Test Information sheet  Prenatal Sample Submission Form  Billing information
Campomelic dysplasia	•Fetal karyotype is 46,XY but ultrasound reveals apparently female or ambiguous genitalia •Limb shortening and/or bowing •Increased nuchal translucency and/or cystic hygroma	SOX9 gene •Full gene sequencing •Deletion/duplication testing	Test Information sheet  Prenatal Sample Submission Form  Billing information
XY Complete or Partial Gonadal Dysgenesis	Fetal karyotype is 46,XY but ultrasound reveals apparently female or ambiguous genitalia.	SRY gene •Full gene sequencing	Test Information sheet  Prenatal Sample Submission Form   Billing information
Anophthalmia / Microphthalmia	•Abnormal inter- and/or intraorbital distance •Absence of globe(s)	•Full Gene Sequencing: SOX2, OTX2 and VSX2 genes •Deletion/duplication testing: SOX2 and OTX2 genes	Test Information sheet  Prenatal Sample Submission Form   Billing information
Zygosity Amniotic Fluid Chorionic Villi Cultured amniotic fluid or CVS	Multiple pregnancies	Zygosity Testing	Test Information sheet  Prenatal Sample Submission Form   Billing information
Miscarriage/Fetal Demise	• Abnormal ultrasound findings • Ambiguous chromosome analysis results • Suspected deletion/duplication syndrome • Miscarriage • Fetal demise	Whole Genome Array CGH for Products of Conception - Whole Genome Array CGH for Products of Conception: custom-designed 180K oligonucleotide array CGH for detection of copy number variants anywhere in the unique sequence of the genome. Includes targeted exon-level coverage of 75 genes associated with neurodevelopmental disorders and 66,000 SNP probes throughout the genome to detect stretches of homozygosity extending 10 Mb or longer.	Test Information sheet  Prenatal Sample Submission Form  Billing information

GeneDx can provide prenatal diagnosis for known familial mutations, in any gene, for families that have had previous testing at GeneDx or elsewhere. For genes not on GeneDx’s standard menu, early preparation is critical.  If all preliminary testing of controls or parents is complete, the turnaround time when testing known familial mutations is usually 2 weeks. Call 301-519-2100 or email prenatal@genedx.com to speak to a genetic counselor in advance.

CLICK HERE TO SEE REQUIREMENTS FOR PRENATAL SPECIMENS.

Prenatal Diagnosis for Known Familial Mutations includes:                                               

• Case-management by a genetic counselor
• Duplicate analysis of fetal specimen
• Maternal cell contamination studies
• Comparison to positive familial controls (required)
• Usually 2-week turnaround if GeneDx has already tested key family members

Choose one of the following links for specific step-by-step instructions

 Known Familial Mutations in Autosomal Recessive Disorders

 Known Familial Mutations in Autosomal Dominant Disorders

 Known Familial Mutations in X-Linked Disorders

 

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