Horizon is an advanced genetic test from Natera that analyzes DNA to determine whether you are a carrier of inherited genetic diseases. This test is specifically designed for couples who are planning a pregnancy or are in the early stages of pregnancy, providing a clear overview of the genetic risk for their child.
Using advanced technology such as Next-Generation Sequencing (NGS), Horizon can analyze a very large number of genes and identify changes (mutations) that may cause no symptoms in the parents but may affect their child.
One of the key advantages of Horizon™ is that it helps identify potential risks before problems occur, giving couples the opportunity to make informed decisions about family planning.
Inheritance: Autosomal Recessive Diseases
There are different ways in which genetic diseases can be passed down or inherited within families. We carry two copies of most of our genes – one copy inherited from our biological mother and one from our biological father.
Some genetic diseases occur when only one of the two copies of a gene has a change (mutation). These are called dominant genetic diseases.
Horizon Carrier Screening does not test for dominant genetic diseases. Horizon Carrier Screening analyzes genetic diseases that occur when both copies of a gene have a change. These are called recessive genetic diseases.
A carrier of a recessive genetic disease is a person who has a change in one copy of a gene, while the other copy is normal. Carriers usually do not have symptoms of the disease.
A couple may have a child with a recessive disease when both the mother and father are carriers of the same genetic disease.
In each pregnancy, a couple in which both parents are carriers of the same condition has:
This is why carrier screening before or during pregnancy can provide couples with important information about their child's genetic risk.
Inheritance: X-Linked Conditions
Some genetic diseases are caused by changes in genes located on the X chromosome. These are known as X-linked conditions and have a specific pattern of inheritance.
The X and Y sex chromosomes determine biological sex:
Because females have two copies of the X chromosome, they also have two copies of the genes located on this chromosome. If one copy of a gene has a change, the other copy may function normally, and the woman may be a carrier of the condition without being affected by the disease.
Males have only one X chromosome. Therefore, if a gene on the X chromosome has a change, they are generally not carriers but may be affected by the disease, as they do not have a second copy of the gene to compensate for the change.
How are these conditions transmitted? When the mother is a carrier of an X-linked condition, there is a specific risk to the child in each pregnancy:
Identifying carrier status before pregnancy through genetic screening tests can provide couples with important information about the risk of passing on certain genetic conditions and help them make informed decisions in consultation with healthcare professionals.
Types of Results
How is the test performed?
Horizon Carrier Screening can be performed by anyone who is pregnant or planning a pregnancy. This test may also be useful for individuals considering egg or sperm donation, as it helps identify the risk of inherited genetic diseases.
Many couples choose to have the test before pregnancy, as the results can help them understand whether there is an increased risk of having a child with a genetic disease. If a potential risk is identified, the couple can discuss different options with their physician or genetic counselor, such as in vitro fertilization (IVF) and genetic testing of embryos. If pregnancy has already begun, Horizon can be performed at any time during pregnancy. Most couples receive results indicating a low risk of having a child with a serious genetic disease.
Horizon helps you and your partner understand the likelihood of passing certain genetic diseases to your child, before or during pregnancy. Many people do not know that they are carriers of a genetic change until they have an affected child. Although no test can identify all possible genetic diseases, carrier screening provides important information to help you make more informed decisions about your reproductive health and family.
If you and your partner are both carriers of the same autosomal recessive genetic change, then in each pregnancy there is:
