What is non-invasive prenatal screening (NIPS)?

FOR FURTHER INFORMATION CONTACT:
Victorian Clinical Genetics Services
Murdoch Childrens Research Institute
Flemington Road, Parkville VIC 3052 Australia
P (03) 8341 6201 W vcgs.org.au
™
NON-INVASIVE PRENATAL SCREENING
ABOUT VCGS
NIPS at VCGS
Victorian Clinical Genetics Services (VCGS) is a not-for-profit provider of
clinical and laboratory genetics services with an emphasis on innovation
and translation of the latest research discoveries into clinical care. Our aims
are to provide the most accurate available information, test interpretations
and counselling to patients so that they can make fully informed choices
regarding their own and their family’s health and wellbeing.
VCGS is offering NIPS using the Panorama™ test from Natera.
Natera is based in California, USA. VCGS is offering Natera’s
Panorama™ Test as we believe it to be the best non-invasive
prenatal screening option currently available. We provide a
comprehensive NIPS service including genetic counselling.
What is non-invasive prenatal screening (NIPS)?
Women of any age and ethnicity can have the Panorama™ test. Some
women have a higher chance of chromosome abnormalities because of
their age, personal or family history, or other screening test results
(ultrasound or first or second trimester maternal serum screen). These
women may choose to have the Panorama™ test to help them decide
if a diagnostic test (i.e. CVS or amniocentesis) is necessary.
Most babies are born healthy, however about four in every one hundred
will be born with a serious health problem and may require medical care.
During pregnancy, testing is available for some conditions caused by
extra or missing chromosomes. Every woman has the choice of whether
or not to have testing during pregnancy to find out her risk of having a
baby with a chromosome condition. NIPS identifies pregnancies where
there is a high risk of having a baby with an extra copy of chromosome 21,
18 or 13, or a missing copy of the X chromosome. This testing will identify
if the pregnancy is high risk for trisomy 21 (Down syndrome), trisomy 18
(Edwards syndrome), trisomy 13 (Patau syndrome) or monosomy X (Turner
syndrome). These are among the most common chromosome conditions
occurring in pregnancy. The test is non-invasive which means that it is safe
for the woman and her baby. It involves a simple blood test for the mother.
The father may provide an optional cheek swab sample, which in certain
circumstances can improve the performance of the test.
How does Natera’s Panorama™ screening
test work?
During pregnancy some DNA from the baby crosses into the mother’s
bloodstream. Panorama™ looks at the baby’s DNA in the mother’s blood
sample to identify certain chromosome conditions that could affect
the baby’s health.
Panorama™ is currently not suitable for women who are carrying more
than one baby (twins, triplets, etc.), or who have used a donor egg or embryo,
or a surrogate or have received a bone marrow transplant. For couples with
close blood relationships, other testing methods may be a better option.
How accurate is the Panorama™ test?
This screening test can identify >99% of pregnancies affected by trisomy 21
(Down syndrome), trisomy 18 and trisomy 13, and 92% of pregnancies with
monosomy X (Turner syndrome). If other sex chromosome conditions (extra or
missing copies of the X and/or Y chromosome) are identified they will be reported
as incidental findings. The sex of the baby can be determined with >99% accuracy.
How does the test process work?
1. Decide whether or not to have the test.
It is your choice whether or not to have the test. Read through the information
provided and discuss this test with your doctor or a genetic counsellor.
If you would like to talk to a genetic counsellor at VCGS about any prenatal
screening or testing options please call (03) 8341 6201. Your doctor or genetic
counsellor will need to complete a test request form for you.
2. Consider whether it is the right time to have the test.
This test can be performed after 9 weeks gestation.
3. Have the blood sample taken.
Sample collection is available from 8:30am-1pm on Mondays, Tuesdays
and Wednesdays at the following locations:
• Royal Children’s Hospital (VCGS)
• The Royal Women’s Hospital (Suite 6)
Who can be tested and when?
Panorama™ can be performed anytime after 9 weeks gestation.
VCGS is accepting samples from women in their first and second
trimesters of pregnancy. Although having the Panorama™ test early
(before 12 weeks pregnancy) can lead to earlier diagnosis, there is
also a higher chance that the laboratory will not obtain a test result
and will request an additional blood sample. For women wanting to
have the Panorama™ test prior to 12 weeks gestation, we recommend
they also have the first trimester combined maternal serum screen.
• Selected St Vincent’s Pathology Collection Centres (see website: vcgs.org.au)
For details of where to go to have your sample(s) taken please speak to
your doctor or a VCGS genetic counsellor (03 8341 6201).
4. Receive your results.
The results will usually be available within 10 days of the sample(s) being
received by the testing laboratory. Your result will be communicated to you
by your doctor or a genetic counsellor. Genetic counselling is available to any
patient having the VCGS NIPS test. Genetic counsellors are trained to talk to
people about genetic conditions and genetic testing, to help make decisions
and to provide support.
FOR FURTHER INFORMATION CONTACT:
Victorian Clinical Genetics Services
Murdoch Childrens Research Institute
Flemington Road, Parkville VIC 3052 Australia
P (03) 8341 6201 W vcgs.org.au
™
UPDATED SEPTEMBER 2013
What is trisomy 21 (Down syndrome)?
What if we receive a low risk result?
Trisomy 21 is caused by an extra copy of chromosome number 21 and is
also known as Down syndrome. This is the most common genetic cause of
intellectual disability. Individuals with Down syndrome all have some degree
of intellectual disability. Some children with Down syndrome have defects
of the heart or other organs that may require surgery or medical treatment.
Some have other medical conditions including hearing or vision loss.
A low risk result means the chance that your baby has one of these four
chromosome conditions is very low and confirmatory testing is NOT necessary.
What is trisomy 18?
Also known as Edwards syndrome, this is caused by an extra copy of
chromosome number 18. This condition causes severe intellectual
disability. Most babies with trisomy 18 have multiple structural
abnormalities of the brain, heart and other organs. Poor growth during
pregnancy is common and many babies are miscarried or stillborn.
Babies born with trisomy 18 usually pass away before one year of age.
What is trisomy 13?
Also known as Patau syndrome, this is caused by an extra copy of
chromosome number 13. This condition causes severe intellectual disability.
Most babies with trisomy 13 have multiple structural abnormalities of the
brain and other organs. Many babies are miscarried or stillborn.
Babies born with trisomy 13 usually pass away before one year of age.
What is monosomy X?
Also called Turner syndrome or 45, X, this is caused by a missing
X chromosome and only affects girls. Girls with monosomy X may
have heart or kidney defects, hearing problems, minor learning difficulties
and are usually shorter than average. Girls with monosomy X may
need growth hormone treatments in early childhood and usually need
sex hormone treatments at the time of puberty. As adults, infertility is
common. Recent studies have demonstrated that early interventions
to address developmental and emotional issues related to monosomy
X can be effective.
What other tests are available?
The Panorama™ test is only one option for identifying pregnancies at
increased risk for fetal chromosome conditions.
It is very important to realise that this test is only for trisomy 21, trisomy 18,
trisomy 13 and monosomy X and that a low risk result does not ensure that
the baby does not have other chromosome conditions.
Invasive diagnostic genetic testing or other testing may still be appropriate
if your baby is found to have ultrasound anomalies, or if there are other
concerns about the health of your baby.
If the test shows we are at ‘high risk’of having
a child with one of these four chromosome
conditions, what happens next?
A genetic counsellor at VCGS will discuss the result with your doctor.
You will be informed of the result either by your doctor or a genetic
counsellor and you will be offered genetic counselling. The genetic
counsellor will talk to you about your results and options for further testing
(CVS or amniocentesis) and can help with making decisions and providing
support. If a diagnostic test confirms the presence of one of these conditions,
you have a choice about whether to continue the pregnancy.
What if no results are obtained?
A ‘no call’ result occurs in 5% of cases and describes the inability to
confidently report a “high risk” or “low risk” test result. Under some
circumstances, the laboratory may request a second patient specimen to
clarify the test results (at no charge). If you decide not to submit an additional
sample for testing, VCGS will refund the full test fee paid.
How much does the Panorama™ test cost?
Your doctor or genetic counsellor will discuss with you the cost of the test.
You will be asked to complete a Payment AuthorisationSlip,whichis
foundatthebottomofthePanorama™test requestform,onthedayof
bloodcollection.Alltestfeesarepayablevia credit card (Mastercard and
Visa) only. The test is not covered by Medicare.
Maternal serum screening and ultrasound. Other screening options
available during pregnancy are first and second trimester maternal serum
screening tests. These can be done instead of, in conjunction with, or prior
to NIPS. Speak to your doctor or a genetic counsellor to discuss which option
might be best for you. For all of these testing options it is your choice whether
or not to have the test/s. VCGS recommends that all pregnant women are
offered maternal serum screening, a 12 week ultrasound scan and an
18-20 week ultrasound scan.
Diagnostic testing. For women who would like more conclusive information
about the baby’s chromosomes, prenatal diagnostic tests (CVS or
amniocentesis) are available and will detect >99% of all chromosome
abnormalities. These tests come with a risk of miscarriage of 1 in 100 (1%)
for CVS and 1 in 200 (0.5%) for amniocentesis. It is important to be aware
that NIPS only screens for the chromosome conditions trisomy 21, trisomy 18,
trisomy 13 and monosomy X. CVS and amniocentesis will provide more
information about the baby’s chromosomes. NIPS is NOT a replacement for
invasive prenatal diagnostic tests.
What if we receive a high risk result?
Contact Details:
A ‘high risk’ result indicates that the test has detected a significantly increased
risk for the baby to have one of these four chromosome conditions. However,
false positive results are known to occur and it is strongly recommended that
you have a diagnostic test (CVS or amniocentesis) to confirm the result. The
specific condition for which the result is high risk will be listed on the report.
Your doctor or genetic counsellor will talk to you about diagnostic tests that
can tell you for certain whether your pregnancy is affected.
VCGS is located on the 4th floor of the Murdoch Childrens Research Institute.
Parking is available at The Royal Children’s Hospital.
Non-Invasive Prenatal Screening Team
p. (03) 8341 6201
f. (03) 8341 6390
w. vcgs.org.au