Niemann Pick Disease
Niemann-Pick disease (NPD) is an autosomal recessive neurodegenerative lysosomal storage disease resulting from the deficiency of the enzyme acid sphingomyelinase. Two types of NPD, Types A and B, have distinct phenotypes and are caused by different mutations in the same SMPD1 gene. NPD-A is more severe and more prevalent in the Ashkenazi Jewish population, with a carrier frequency of approximately 1 in 115. Features include loss of brain function and hepatosplenomegaly. Average life expectancy for NPD-A is 2-3 years of age. Three mutations causing NPD-A account for the majority of Ashkenazi Jewish NPD carriers [p.L304P (L302P), c.996delC (fsP330), p.R498L (R496L)]. A panethnic recurrent mutation causing NPD Type B [p.R610del (delR608)] is also tested. Screening for these four mutations is expected to detect approximately 97% of carriers in the Ashkenazi Jewish population. The American College of Medical Genetics recommends that carrier screening for NPD be offered to individuals with at least one grandparent of Eastern European (Ashkenazi) Jewish ancestry before/during pregnancy.
Full gene sequencing is available for reproductive partners of known mutation carriers. Prenatal diagnosis is also available. Prior to ordering prenatal testing, please contact our laboratory at 212-241-7518 to discuss.
1. Levran O, et al. Proc. Natl. Acad. Sci, USA. 88:3748-3752.
2. Levran O, et al. Blood, 80:2081-2087, 1992.
3. Levran O, et al. Hum. Mut. 2:317-319, 1993.
4. Scott, S.A., Edelmann, L., Liu, L., Luo, M., Desnick, R.J. and Kornreich, R. Experience with carrier screening and prenatal diagnosis for sixteen Ashkenazi Jewish Genetic Diseases. Hum. Mutat. 31:1-11, 2010.
Post-natal: Two 5-10 mL tubes of anticoagulated blood in EDTA (lavender top) or two 5-10 mL tubes of anticoagulated blood in ACD (yellow top).
- Chorionic Villi: 5-10 mg in conical tube with sterile saline OR transport media
- Amniotic Fluid: 10 ml in conical tube
- Cultured Cells: two confluent T-25 flasks
Additonally, please send:
- 5-10 ml maternal blood in EDTA (lavender top) required to perform MCC studies on all prenatal samples and in case maternal confirmation studies are necessary
- 5-10 ml paternal blood in EDTA (lavender top) in case paternal confirmation studies are necessary
Shipping: Ship at room temperature.
Turnaround Time: 10-14 days
CPT Code: 81330
Consent and requisition forms: Carrier Screening Requisition and Consent [PDF]
Additional information: Expanded Ashkenazi Jewish Carrier Screening brochure [PDF]
Related Tests: Ashkenazi Jewish Carrier Screening Panel