Prenatal Chromosome Analysis – Chorionic Villus Sampling (CVS)

Clinical info Chorionic villus sampling is a method for first trimester prenatal diagnosis of chromosome disorders. Chromosome analysis is performed on a villus biopsy by harvest following a short-term culture. CVS is performed earlier in pregnancy than amniocentesis. There is a 1-2% chance for a mosaic result from CVS, which necessitates follow-up amniocentesis for confirmation or clarification. While CVS has the advantage of providing an earlier result to the mother, the CVS procedure does not permit analysis of alpha-fetoprotein. Therefore, if the indication for study is increased risk of a neural tube defect, the amniocentesis rather than CVS would be recommended. Routine chromosomes and FISH trisomy screen for 13, 18, and 21 are available for prenatal samples.
Indications
  • Couples at increased risk of having infants with abnormal chromosomes
  • Advanced maternal age - 35 years or older
  • Previous child with a chromosome disorder such as Down syndrome
  • One member of the couple is known to carry a chromosome rearrangement
  • In certain cases, relatives of a child with a chromosome disorder
  • Couples at risk for having children with X-linked disorders for which molecular testing may not be available.
  • Pregnancies at increased risk of chromosome defects due to finding of fetal defects on ultrasound.
  • Pregnancies identified by prenatal serum screening to be at increased risk for neural tube defects or chromosome defects.
Specimen Requirements 5-10 mg of chorionic villi obtained in 10 ml of transport media. The following information should accompany the specimen: patient's name, physician's name, date collected, EGA by ultrasound, LMP (if available), maternal age, and indication for study. Sterile tubes, transport media, and mailers are available from the Greenwood Genetic Center. Cultured flasks may also be sent. Please send 2x T25 confluent flasks
Transport Specimen should be kept at room temperature; do not freeze or refrigerate. Specimen should be sent by courier or overnight mail to arrive at the laboratory within 24 hours.
Turnaround time 14 days
Cell culture can take 1-4 weeks and may lengthen turnaround time.
Aneuvysion FISH results are usually available within 1-2 days
CPT Codes Chromosomes: 88235, 88267, 88280, 88285, 88291
FISH: 88235, 88275, 88271x4, 88291
Cost Chromosomes: $1304
FISH Trisomy screen: $1094.00
Contact For further information contact Kellie King, MS , Lab Counselor or Barb DuPont,PhD, Cytogenetics Laboratory Director at 1-800-473-9411

Cytogenetics Lab

The Cytogenetics Lab provides high quality analysis for the detection of both constitutional chromosomal aberrations as well as abnormalities related to hematological malignancies

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