Niemann-pick types a/b

Newborn screening is a state run program that screens babies at birth for certain serious medical conditions. In most states, there is no newborn screening for Niemann-Pick disease (SMPD1-associated). However, as of June 2016, the state of New York is testing out having this condition on their newborn screening panel (both type A and type B). Missouri and Illinois also are testing for Niemann-Pick disease (SMPD1-associated). Other states are also considering adding it to their screening panel.

There is more than one way to have genetic testing for Niemann-Pick disease (SMPD1-associated). The different types include:

• Single gene testing: genetic testing for the SMPD1 gene only. This is especially helpful for people who have a family history of the condition or who are from populations where this condition is more common (e.g. Ashkenazi Jewish). This testing can either be targeted (looks for a specific genetic change/mutation), sequence analysis (reads the entire gene code to look for a spelling mistakes/changes), or deletion/duplication testing (looks for large missing or extra pieces in the gene code). There are 3 specific changes/mutations in the SMPD1 gene that account for 90% of the mutations in the Ashkenazi Jewish population.
• Multi-gene panel: includes the SMPD1 gene and other genes that cause conditions with similar symptoms. This is most helpful when a doctor thinks a person could have Niemann-Pick disease (SMPD1-associated) but is not completely sure.

Both genetic testing and the enzyme function testing for Niemann-Pick disease (SMPD1-associated) can be done on blood. Therefore, it is not necessary to have a bone marrow, liver, or other biopsy to do either of these tests.

Because Niemann-Pick disease (SMPD1-associated) is a genetic condition, the gene changes/mutations in the SMPD1 gene that cause it can be passed down from one family member to the next. This means that if someone in the family is diagnosed with Niemann-Pick disease (SMPD1-associated), other blood relatives have a chance of having one of the same gene changes/mutations identified in the person with Niemann-Pick disease (SMPD1-associated). Any blood can be tested to see if they have one of the same identified changes/mutations. This is called "carrier testing". The closer related you are to a person with Niemann-Pick disease (SMPD1-associated), the higher your chances of being a carrier. For example, this means that the sister of a person with Niemann-Pick disease (SMPD1-associated) has a greater chance of being a carrier than a cousin.

There is prenatal testing available for pregnancies that are at an increased risk of having a child with Niemann-Pick disease (SMPD1-associated). This testing can either be done through genetic testing (if the changes/mutations in SMPD1 gene in the family are known) or by testing the enzyme activity in the fetus. Preimplantation genetic diagnosis (PGD) in which embryos can be genetically tested is also available.

To find a genetic counselor near you who can discuss prenatal testing, visit the National Society of Genetic Counselors Find a Genetic Counselor website.

If someone in your family has Niemann-Pick disease (SMPD1-associated), you may consider testing to see if you are a carrier for the genetic changes/mutations in the SMPD1 gene that have been identified in the family. Carrier testing must be done by genetic testing. Enzyme function testing cannot be used to see if someone is a carrier.

To find a genetic counselor near you who can discuss carrier testing, visit the National Society of Genetic Counselors Find a Genetic Counselor website.