Horizon Advanced Carrier Screening | Clinician Information | Natera


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Horizon carrier screening experience across 380,000+ patients

The Horizon difference

Clinical features

  • Horizon screens for 274 conditions. The five-panel and à la carte ordering options enable you to screen for just what the guidelines recommend or for a broad number of conditions.
  • Horizon is one of the first tests to screen for Duchenne muscular dystrophy (DMD). DMD is more common than SMA and fragile X and has an incidence similar to cystic fibrosis.
  • Horizon refines your patients’ risks. Fragile X automatic AGG interruption testing, enhanced spinal muscular atrophy (SMA) screening, and Tay-Sachs enzyme testing provide you with more information than standard screening.

Learn more: Download SMA White Paper

Learn more: Download DMD White Paper


Why offer screening for inherited conditions?

When two people are carriers for the same autosomal-recessive condition, they have a 25% chance of having an affected child during each pregnancy. For X-linked conditions, only the mother needs to be a carrier for there to be a risk of passing on the condition to the child. Knowing their carrier status allows couples to consider pre-pregnancy reproductive options such as preimplantation genetic testing (PGT) or plan for the birth of a child with a genetic condition.

Following best practices

Horizon was developed to allow healthcare providers to offer carrier screening for conditions that are currently recommended by the following professional medical societies:

  • The American College of Medical Genetics and Genomics (ACMG)
  • The American Congress of Obstetricians and Gynecologists (ACOG)
  • The Victor Center for the Prevention of Jewish Genetic Diseases

Each organization recommends screening the general population or specific ethnic groups for certain conditions, based on carrier frequencies, incidence rates, and other criteria.

Product support

  • Horizon can be used with both saliva and blood samples. Kits can be stored in your office at room temperature. We provide complimentary, on-demand shipping to and from your clinic.
  • Genetic counselors are here to support your practice. At no additional cost, board-certified genetic counselors are available to answer any questions about Horizon that you or your patients may have.
  • Tools and resources are available throughout the process, including mobile phlebotomy services, patient and physician portals, and EMR integration.



Panel options for every patient

Panels / Number of conditions Suitable for
Horizon 4 Patients of any ethnic background
Horizon 14 Patients of any ethnic background
Horizon 27 Patients of any ethnic background
Horizon 106 Patients of Ashkenazi or Sephardic Jewish descent
Horizon 274 Patients of any ethnic background OR Jewish patients who prefer more coverage than Horizon 106
A la Carte: Cystic Fibrosis,
Spinal Muscular Atrophy, and/or
Tay-Sachs Enzyme
Patients of any ethnic background


View conditions list

Combined methodologies, improved sensitivity

Horizon uses various methodologies to identify carriers of different types of genetic variants. These methods are often used in combination to increase test sensitivity. Horizon employs the following methods:

Combined Methodologies

Copy number analysis

Variations in the number of copies of certain genes or regions of genes can have clinical implications. Several methods may be used to detect variations in copy number, including multiplex ligation-dependent probe amplification and fluorescent quantitative polymerase chain reaction (PCR). These methodologies can be used to identify deletions and duplications or to quantify the amount of DNA present in a region of interest.

Next-generation sequencing

The sequenced DNA is compared to a reference genome to identify any variation. The significance of any variants is determined based upon a combination of several sources of information, including current knowledge of the variants themselves and predicted effects of the variation upon gene function. In accordance with ACMG guidelines, only variants determined to be pathogenic or likely pathogenic are reported. Variants determined to be benign or of uncertain clinical significance are not reported.

Polymerase chain reaction

Polymerase chain reaction (PCR) is a process by which a small region of DNA is cloned and amplified for the purpose of sequencing. By amplifying a specific region of DNA, multiple copies of the area of interest are available for DNA analysis. A type of PCR, in conjunction with capillary electrophoresis, is performed for detection of carriers of fragile X syndrome.


Genotyping may be performed for genes and regions of DNA that are not amenable to next-generation sequencing. It may also be used for purposes of quality control.

Sanger sequencing

Sanger sequencing is used as appropriate to confirm the presence of genetic variants identified using other methods. This method allows for an in-depth look at specific regions of DNA.

More information

Contact us for descriptions of the methods used for specific conditions. Carrier rates, detection rates, and residual risk rates are available.

Contact Us

What if My Patient is a Carrier

Non-pregnant Carriers: Recessive Conditions

If your patient is a carrier for a specific autosomal recessive condition it is recommended that the partner be screened for the same condition. If the partner is a carrier for the same condition, referral for formal genetic counseling should be considered. Couples at risk to have a baby with an autosomal recessive disease can consider several reproductive options including:

  • natural pregnancy, with or without prenatal diagnosis
  • preimplantation genetic testing (PGT) with in vitro fertilization (IVF) to test and then transfer embryos that are free of the condition
  • the use of a sperm or egg donor
  • adoption

Non-pregnant Carriers: X-Linked Conditions

Partner screening is not often recommended as a next step for carriers for of X-linked conditions because only the mother needs to be a carrier for the condition to be passed to the child. You may wish to discuss available reproductive options with your patient, including preimplantation genetic testing (PGT) with in vitro fertilization (IVF), adoption, using an egg donor, or prenatal diagnosis.

Pregnant Carriers: Recessive Conditions

If your patient is a carrier for a specific autosomal recessive condition it is recommended that the partner be screened for the same condition. If the partner is a carrier for the same condition, referral for formal genetic counseling should be considered. Couples at risk to have a baby with an autosomal recessive disease can consider invasive prenatal diagnosis using chorionic villus sampling or amniocentesis. Alternatively, the couple may choose to delay testing until after delivery.

Pregnant Carriers: X-Linked Conditions

If your patient is pregnant and found to be a carrier for an X-linked recessive condition, referral for genetic counseling should be suggested. Fetal gender can be confirmed using Panorama, a simple blood test from the mother. Alternatively, some couples will choose to have a diagnostic test such as chorionic villus sampling or amniocentesis. Diagnostic testing can also be performed after the baby is delivered.

The Horizon Process

Physician orders Horizon

Blood or saliva sample collected

Sample shipped to Natera and analyzed

Results sent to physician in about 2 weeks


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