A comprehensive guide on Carrier Screening

You may perhaps be seeking valuable information on carrier screening. This genetic test is generally conducted on healthy people to determine if they are a carrier of some dreadful recessive genetic disease. The carrier screening test when conducted can offer life-long information concerning the person’s reproductive risks faced. It also shows if the child they bear will have a genetic disease or not. 

About recessive genetic disease

This disease generally occurs if a mutation is present within the genes of the pair. Generally, one gene is inherited from the father and the other from the mother. 

According to medical experts, some people might become carriers of disease-causing changes, even without their knowledge. In case both partners become carriers, then the chances of affecting the child with the recessive genetic disease become 25%. Again, 50% of such children are likely to become carriers as they grow up. 

Autosomal recessive disorder

When an autosomal disorder is a concern, both parents are found to become carriers of similar genetic diseases. In this case, bearing an affected child with each pregnancy is slated at 25% risk. 

  • 50% chance states that the child is not likely to inherit from either parent defected genet with mutation. He/she will also not become a carrier, thus not being affected by this disorder.
  • 50% chance states that the child might become a carrier, but without displaying any symptoms. The child is likely to inherit one mutated gene and one normal gene. 
  • 25% chance states that the child could be born, but with an autosomal recessive disorder. In this case, he/she is likely to have inherited around 2 changed mutated genes from both parents. 

X-linked recessive disorder

If the carrier is the mother, then a 25% chance is there of delivering an affected male baby in each pregnancy. 

  • 25% chance is there of delivering an affected male baby with just a single mutated gene copy. 
  • 25% chance is there of the female child being a healthy carrier or mildly affected one. 
  • 50% chance is there of the female or male child being delivered, who is healthy, but exhibits a particular gene normal copy. 

What are the benefits of undergoing the Carrier Screening Test?

By conducting this special test, partners can make well-informed choices concerning family planning. They may do the following:

  • Pursue available alternate options like adopting a baby or using an egg donor or a sperm. 
  • Plan pregnancy using PGD (pre-implantation genetic diagnosis) method. 
  • Avail specialist care throughout the pregnancy stage and delivery.
  • Prenatal diagnosis at the time of pregnancy.
  • If possible prepare for efficient management and treatment of the affected baby. 

What reports are offered with career screening?

The screening panel generally includes inherited conditions, including the following:

  • Cystic fibrosis
  • Alpha thalassemia
  • Spinal muscular atrophy
  • Fragile X syndrome

When to avail of the screening test?

Pre-pregnancy is considered to be the ideal time to get the screening test. However, testing can be done before, during, or even after pregnancy. But if it is done before conception, it allows the couples to make proper plans based on the available options. 

Whom to discuss with to seek more valuable information?

It will be wise to consult your genetic counselor or general physician about carrier screening. The medical experts can answer all your queries correctly. After pre-test genetic counseling, the physician might advise you to get the test complete. 

Can both partners get screening simultaneously?

Yes! Many labs do offer partner and individual testing options to choose from. 

What samples are to be submitted?

You may get a kit as referred by your doctor to obtain your DNA sample for testing purposes. 

How much time does it take to get the results?

The lab usually sends test results within 15 business days from the date of receiving the sample. 

Will there be needed frequent carrier screening?

Both partners require undergoing this test just once in a lifetime. But if you are detected to be a carrier as well as have a new partner, then your new partner will also require undergoing this test. 

What are the chances of delivering an affected child if you are found to be the carrier?

In case you are confirming to be an autosomal recessive disorder carrier, then it becomes essential to determine the carrier status of your partner. In case both of you are found to be carriers for similar genetic conditions, the chances of having an affected child with this disorder become 25%.

If the female declares an X-link recessive disorder carrier, then the chances of the male baby with a single mutated gene copy becomes 50%.

What are your reproductive options if you are declared a carrier?

If the test conducted reveals both of you to be the carrier of this genetic disease, then you need to be aware of the available options. Discussing with your medical expert will provide you with viable options.