Fragile X Syndrome Screen

With over 99% accuracy, the NxGen MDx screen for fragile X syndrome is one of the world’s most accurate tests for detecting genetic markers that may affect pregnancy and future child development.

Fragile X Syndrome Screen

What Is It?

Fragile X syndrome affects approximately 1 in 4,000 males and 1 in 8,000 females. The majority of males with fragile X syndrome have a significant intellectual disability. The spectrum ranges from learning disabilities to severe mental retardation and autism. About one third of the females affected with fragile X syndrome have a significant intellectual disability. Others may have more moderate or mild learning difficulties. To learn more about fragile X syndrome, view or download the Fact Sheet.

Who Should Take It?

• All individuals of child bearing age, regardless of gender
• All individuals with a family history of genetic disorders
• All individuals with partners who are carriers of a genetic disorder
• Couples or individuals considering in vitro fertilization
• Pregnant women

Why NxGen?

When testing, our laboratory analyzes all of the coding DNA in a gene to determine if any disease-causing pathogenic variants are present. By sequencing all of the coding DNA in a gene, instead of just a portion, we are able to offer the most accurate genetic testing available, regardless of your ethnicity. The majority of laboratories are only sequencing a portion of the gene, leaving room for error with missed pathogenic variants, especially when testing a variety of ethnicities. By sequencing the entire gene, NxGen MDx testing eliminates the doubt in a negative result and drastically reduces the residual risk, regardless of ethnicity.

Test References:

  1. Chen et al. (2010).  An information-rich CGG repeat primed PCR that detects the full range of fragile X expanded alleles and minimizes the need for Southern blot analysis.  J Mol Diagn, 12:589-600.
  2. Cornish et al. (2004).  Annotation: Deconstructing the attention deficit in fragile X syndrome: a developmental neuropsychological approach.  J Child Psychol Psychiatry, 45(6):1042-1053.
  3. Cronister et al. (2008).  Prevalence and instability of fragile X alleles: implications for offering fragile X prenatal diagnosis.  Obstet Gynecol, 111:596-601.
  4. Eichler et al. (1994).  Length of uninterrupted CGG repeats determines instability in the FMR1 gene.  Nat Genet, 8:88-94.
  5. Fernandez-Carvajal et al. (2009).  Expansion of an FMR1 grey-zone allele to a full mutation in two generations.  J Mol Diagn, 11:306-1310.
  6. Hagerman et al. (2002).  Fragile X syndrome : Diagnosis, treatment, and research; 3rd ed.; Baltimore : Johns Hopkins University Press.
  7. Hagerman and Hagerman (2004).  The fragile-X premutation: a maturing perspective. Am J Hum Genet, 74(5):805-16.  Epub 2004 Mar 29. Review. Erratum in: Am J Hum Genet. 2004 Aug;75(2):352.
  8. Hagerman (2006).  Lessons from fragile X regarding neurobiology, autism, and neurodegeneration.  J Dev Behav Pediatr, 27(1):63-74.
  9. Hantash et al. (2011).  FMR1 premutation carrier frequency in patients undergoing routine population-based carrier screening: insights into the prevalence of fragile X syndrome, fragile X-associated tremor/ataxia syndrome, and fragile X-associated primary ovarian insufficiency in the United States.  Genet Med, 13:39-45.
  10. Jacquemont et al. (2007).  Fragile-X syndrome and fragile X-associated tremor/ataxia syndrome: two faces of FMR1.  Lancet Neurol, 6(1):45-55.
  11. Koukoui and Chaudhuri (2007).  Neuroanatomical, molecular genetic, and behavioral correlates of fragile X syndrome.  Brain Res Rev, 53(1):27-38.
  12. Nolin et al. (2003).  Expansion of the fragile X CGG repeat in females with premutation or intermediate alleles.  J Hum Genet, 2003, 72:454-464.
  13. Sherman et al. (2005).  Fragile X syndrome: diagnostic and carrier testing.  Genet Med, 7(8):584-587.
  14. Strom et al. (2007).  Molecular testing for Fragile X Syndrome: lessons learned from 119,232 tests performed in a clinical laboratory.  Genet Med, 9:46-51.
  15. Terracciano et al. (2005).  Fragile X syndrome.  Am J Med Genet C Semin Med Genet, 15;137(1):32-37.
  16. Van Esch (2006).  The Fragile X premutation: new insights and clinical consequences.  Eur J Med Genet, 49(1):1-8.
  17. Willemsen et al. (2004).  The fragile X syndrome: from molecular genetics to neurobiology.  Ment Retard Dev Disabil Res Rev, 10(1):60-67.

Talk to a Genetic Counselor

As a NxGen client, you'll have access to personal genetic counselors who can help explain the results of your screens and provide insight on how to move forward. To schedule a personal conference to discuss your screen results, call (855) 776-9436. or click the link below.

Discuss Your Screening Results

Connect With Our Customer Care Center

Get answers to all your questions related to billing, insurance coverage, the status of your screening results, and more by calling us at (855) 776-9436 or clicking the link below.

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