Genetic Screening

There is a great variety of conditions which have a genetic basis, and for which a positive family history of the condition increases an individual's risk of developing the same disease.

There are 2 steps involved in determining the possibility that genetic changes are present in either themselves, or their unborn child. Intercare Salubrity can provide assistance with both:

1. Exploration of the family history

This should be done in consultation with a healthcare practitioner such as General Practitioner or Genetic Counsellor. They will try and construct a picture of your ancestry, the number of individuals affected and the types of conditions they suffered from, age of onset and/or death and their gender. Based on the findings of this, a more informed decision to perform further genetic testing can be made.

2. Genetic testing and screening

Here, a sample of the individuals DNA is obtained (usually a swab from the inside of the cheek or a blood sample) and then analysed to identify any changes to the DNA which are known to increase the risk of developing the disease in question.

Two of the most common genetic tests or screenings which are done are related to breast and ovarian cancer risk, as well screening for Down Syndrome and other related conditions in an unborn child.

Intercare Salubrity offers both of these services. For information on each, please see below:

Genetic screening for breast cancer

Intercare Salubrity offers genetic testing which detects DNA changes that increase the risk of Breast cancer, as well as potentially playing a role in other cancers such as Ovarian and Prostate cancer.

Genetic testing for Down Syndrome and related conditions

Salubrity offers prenatal screening for Down Syndrome and other conditions caused by abnormal numbers of chromosomes, through a technique called Non-Invasive Prenatal Testing (NIPT).

What is Non-Invasive Prenatal Testing (NIPT)?

Researchers have discovered that fetal DNA enters the mother’s circulation from the 5th week of pregnancy. This can be obtained by simply drawing blood from the mother, as would normally be done for any other test (such as a glucose or cholesterol test). Non-Invasive Prenatal Testing (NIPT) is the method of collecting this blood, isolating the fetuses DNA from it and then testing it for abnormalities.

 

 

What are the advantages of NIPT over the standard screening approaches?

NIPT offers several advantages:

  1.      Because the test utilizes DNA from the fetus itself obtained directly from the mothers bloodstream, it is a more direct approach to assessing the presence of such a condition, as it looks at the root of the problem (the DNA) rather than a proxy for the condition (such as certain physical features on ultrasound or raised levels of substances in the mothers blood).

 

  1.      NIPT is much more accurate and reliable than the standard methods of screening. With maternal serum testing, 19 in every 20 women who test positive do not actually have a child with Down Syndrome (meaning 19 women undergo the invasive tests unnecessarily!). Conversely, of every 20 women who test negative, 3-4 actually have a child with the condition (meaning 3-4 “missed” cases of Down Syndrome per 20 tests). In comparison, NIPT will be correct in up to 99.9% of cases.  

 

  1.      The amount of fetal DNA in the maternal bloodstream is sufficient for testing from the 9th week of gestation. This is earlier than the other methods of assessing for the presence of these conditions, such as nuchal translucency ultrasound, a CVS or amniocentesis.

 

The end result of this is 2 major benefits:

- Testing can be done earlier. This leaves the parents with more time to process the result, make decisions and plan for the child's care should the result be abnormal.

- Avoidance of unnecessary invasive testing. By avoiding the false results sometimes produced by traditional screening methods, it ensures only those mothers who absolutely need further testing undergo it.

Does this test only screen for Down Syndrome?

No. It can detect the following conditions in addition to Down Syndrome:

  • Trisomy 18 (Edwards Syndrome)
  • Trisomy 13 (Patau Syndrome)
  • Monosomy X (Turner Syndrome)
  • Triple X
  • Klinefelter Syndrome
  • Jacobs Syndrome
  • Fetal Gender

What is the general process for undergoing one of these tests with Intercare Salubrity?

The process consists of 3 simple steps.

  1.      Have a discussion with one of our network Genetic Counsellors. This may be in person, via telephone or Skype.
  2.      Have your DNA sample taken at one of our practices (this is via a gentle swab from inside your mouth or a normal blood test). From here it is sent to Switzerland for testing.
  3.      Come back in 2 weeks and review the results with your doctor and genetic counsellor.

 

I would like to have genetic screening done or speak to a Genetic Counsellor, what do I do now?

Please contact Intercare Salubrity via one of the following channels:

  •   Call 086 999 0669
  •   Send an email with your name and telephone number to genetics@salubrity.co.za and we will contact you within 24 hours.
  •   Send an SMS with the word “Salubrity" followed by your name the word "Genetics" to 31000 and we will call you back

(SMS costs R1.50, free and standard SMS’s do not apply).