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> Chromosomal Analysis

> FISH

> Parentage

MOLECULAR ANALYSIS:

Ashkenazi Jewish Genetic Screening - Panel 1

A number of autosomal recessive disorders are found at higher frequencies in the Ashkenazi Jewish population. Most of these disorders are untreatable neurodegenerative diseases that result in reduced life expectancy. The American College of Obstetricians and Gynecologists recommends that individuals of Ashkenazi Jewish descent be offered genetic screening for cystic fibrosis, Tay-Sachs disease, Canavan disease, and familial dysautonomia as part of routine obstetric care. The aggregate carrier risk for these disorders in the Ashkenazi Jewish population is approximately 12%. Additional carrier screening tests for other disorders are also available. See Ashkenazi Jewish Genetic Screening - Panel 2 and Gaucher Disease Carrier Testing for testing information.

Indications for Testing

• Carrier screening
• Gamete donors

Testing Methodology

Direct mutation analysis: For CF, the CF-Oligonucleotide Ligation Assay is used to detect a panel of 31 mutations in the CFTR gene including 5 mutations relevant to the Ashkenazi Jewish population. For TSD, CD, and FD, Amplification Refractory Mutation System (ARMS) technology is used to screen for 7 relevant mutations. The ARMS test also includes screening for the single relevant mutation found in Fanconi anemia group C:

*The carrier detection rate for Tay-Sachs disease is maximized by combining DNA analysis with biochemical analysis for hexosaminidase A. Biochemical analysis for hexosaminidase A is the appropriate test for individuals of French Canadian and Cajun descent. See Tay-Sachs Disease Carrier Testing-Biochemical Analysis for testing information.

Sensitivity

Carrier detection rates in the Ashkenazi Jewish population:

• Cystic fibrosis 97%
• Tay-Sachs disease 94% (DNA analysis),98% (DNA and biochemical analysis)
• Canavan disease 97%
• Familial dysautonomia 99%
• Fanconi anemia group C 99%

This carrier screening test is most appropriate for individuals of Ashkenazi Jewish descent. This test may not be appropriate for individuals from other ethnic backgrounds. The sensitivity of this carrier screen in non-Jewish populations has not been established. This test is not appropriate for fetal diagnosis or diagnosis of individuals with clinical phenotype.

Specimen Requirements

Blood: 5 cc collected in a purple top (EDTA) or yellow top (acid citrate dextrose) vacutainer tube. Do not centrifuge or freeze. Sample may be refrigerated or stored at room temperature.

Turnaround Time

14 days

CPT Codes

Panel 1: 83891, 83894, 83900, 83901 (2X), 83909, 83912, 83914 (2X)

Panel 1 and 2: 83891, 83894 (2X), 83900, 83901 (4X), 83909, 83912, 83914 (4X)

Forms and Transport & Shipping Informtaion

> Medical Genetics Test Requisition Form

> Standard DNA Consent Form

> Medical Genetics Specimen Transport and Shipping Information