FAQs

A detailed description of the PGT[SR]Seq method and its requirements is given in the Juno Genetics User Manual. In brief, Juno can undertake a new PGT[SR]Seq case once a genetic report describing the chromosomal rearrangement has been received and a Juno scientist has confirmed that PGT[SR]Seq is technically possible. A completed Requisition Form, formally requesting PGT[SR]Seq and providing relevant information concerning the patients, is also required. Rarely, PGT[SR]Seq is not technically possible. For this reason, patients should not begin a cycle until Juno has reviewed the patient’s genetic report and confirmed that PGT[SR]Seq is feasible.

Genetic tests, such as GeneSeeker, analyze genes, which are chemical instructions encoded in our DNA. The genes are the blueprints for building our bodies and maintaining the health of our cells, tissues and organs. Genetic testing looks for variations in your genes (mutations) that can cause genes to stop working properly, potentially lead to disease. There are various reasons why you or your healthcare provider might consider genetic testing, such as assessing the risk of you and your partner having a child affected by an inherited disorder, or to determine the cause of an inherited condition that runs in your family.

It has been estimated that everyone carriers 3‐5 genetic mutations but in most cases these do not cause a disease. This is because we each have two copies of every gene (with the exception of genes on the X-chromosome in men). The GeneSeeker test looks at variations in the DNA which are ‘recessive’, meaning that they only cause a disease when both copies of the gene have a mutation. If you have a recessive mutation in one copy of a gene, stopping it from working properly, the other (normal) copy is sufficient to prevent the disease. However, if your partner carries a mutation in the same gene, then there is a risk that a future child could receive a defective copy from each of you, leaving them with no functioning copies of the gene, and causing them to develop an inherited disorder.

Most carriers of recessive gene mutations have no family history of inherited disease. Such disorders can remain hidden in families for hundreds of years before suddenly and unexpectedly reappearing. We are all carriers of recessive mutations, but we do not realise it because we have two copies of each of our genes (with the exception of X-chromosome genes in males). Having one defective copy is not sufficient to cause disease. To have a recessive inherited disease both copies of the gene must be knocked out by mutation. GeneSeeker can look for hidden recessive mutations carried by you and your partner and identify whether you have any in the same gene. In such cases, there is a risk that you could each pass a defective copy of the gene to a future child, meaning that they would have no functional copy of the gene and would develop an inherited disorder.

Regardless of whether you are planning to get pregnant naturally or whether you intend to use assisted reproductive treatments (e.g. IVF), GeneSeeker can help to identify whether you and your partner have an increased risk of having a child affected by an inherited disorder. If you are both found to carry mutations in the same gene, there is a risk that a future child could inherit a defective copy of the gene from each of you, leading to the child being affected. If you find you are at increased risk of producing an affected child, there are strategies that can help avoid an affected pregnancy and/or birth, such as preimplantation genetic testing or prenatal testing.

We are all carriers of recessive genetic mutations and it is likely your baby will be too. However, being a carrier of a recessive mutation does not mean that the baby will be affected by an inherited disorder. We have two copies of each of our genes (with the exception of genes on the X-chromosome for men). If you have a recessive mutation in one copy of a gene, stopping it from working properly, the other (normal) copy is sufficient to prevent the disease.

GeneSeeker results are typically ready within 4 weeks of Juno Genetics receiving your blood sample.

In the vast majority of cases, the answer is no. We have two copies of each of our genes (with the exception of genes on the X-chromosome for men). The GeneSeeker test looks at variations in the DNA which are ‘recessive’, meaning that they only cause a disease when both copies of the gene have a mutation. If you have a recessive mutation in one copy of a gene, stopping it from working properly, the other (normal) copy is sufficient to prevent the disease. However, if your partner carries a mutation in the same gene, then there is a risk that a future child could receive a defective copy from each of you, leaving them with no functioning copies of the gene, and causing them to develop an inherited disorder.

PGT[A]Seq results are typically available 6 days after Juno receives the embryo biopsy samples (although results can take up to 10 days).

The development of a new PGT-M test usually requires 3 weeks starting from the date that Juno receives all of the necessary DNA samples and paperwork, but can take up to 6 weeks in some cases. Once Juno has confirmed that the test is ready, the IVF cycle can begin. The embryos produced can be biopsied and the specimens sent to Juno. PGT[M]Seq results are generally available 9 days after Juno receives the embryo biopsy samples (although can take up to 14 days).

In some cases, embryos contain a mixture of cells, some having the correct number of chromosomes and others having an abnormal chromosome number. Such embryos are said to be ‘mosaic’. Some studies have suggested that mosaic embryos are less likely to produce a healthy pregnancy than those that have only normal cells in their biopsy specimen. However, other studies have provided contradictory information. The PGT[A]seq method used by Juno Genetics reveals when an embryo sample contains a mixture normal and abnormal cells. Any mosaic embryos detected during PGT-A will be indicated in the report issued by Juno. The choice of whether or not mosaic embryos are transferred to the uterus depends on the policy of the IVF clinic as well as national guidelines. It is recommended that transfer is considered only after consultation with a qualified healthcare professional.

We aim to make working with Juno Genetics as easy as possible. Juno is committed to supporting the clinics it works with, providing guidance at all stages of the PGT process. We are available seven days a week to assist with queries or to provide advice. At Juno we appreciate that different clinics may have unique needs and our policy is one of flexibility, where we adapt to the specific requirements of each clinic. If your clinic already offers PGT in collaboration with another genetics laboratory, then it is likely that very few significant changes, if any, will be necessary. Please contact Juno Genetics and we will be happy to walk you through the enrolment procedure, provide all necessary documentation and answer any questions you might have. If your clinic is new to PGT, Juno can help by providing valuable information and documentation to get you started. Juno can also assist with training and evaluation of procedures, making sure that all elements of the PGT procedure are optimised and working well, prior to the launch of a clinical service. Please contact supportuk@junogenetics.com to begin working with Juno.

If the proportion of samples that fail to give a PGT result is consistently higher than expected, this is almost always due to a problem with technique used for the cell washing and loading or, less commonly, with the embryo biopsy method. Scientists at Juno Genetics have decades of experience working with clinics in order to achieve optimal PGT results and can assist with troubleshooting. Problems are almost always solved after simple and easy to implement changes to procedure.

Juno Genetics harnesses the power of the very latest DNA sequencing technologies to deliver a best-in-class test for chromosome abnormalities, called PGT[A]seq. Not only does PGT[A]seq measure the amount of DNA from each chromosome with unprecedented accuracy, allowing the number of copies of each chromosome to be determined in the embryo biopsy specimen, but it also detects thousands of variations in the sequence of the DNA from the embryo (known as polymorphisms). Juno was one of the first laboratories in the world to add polymorphism analysis to a PGT-A test. The extra information provided by DNA polymorphisms allows detection of important chromosome abnormalities that are invisible to other PGT-A methods, including triploidy, a common cause of miscarriage. Clinical studies have shown that the Juno PGT[A]seq method succeeds in providing valuable predictive information about an embryo’s capacity to produce a healthy birth, helping to avoid the transfer of abnormal embryos, which will fail to implant, miscarry or produce children affected by chromosomal abnormalities.

Many of the advanced PGT methods used by Juno Genetics are available nowhere else in the world. Consequently, it is necessary to send samples to the Juno laboratory (in Oxford, UK) in order to access the tests. In most cases, the time required for the shipping of samples, and for the complex laboratory procedures, means that embryos must be cryopreserved (vitrified) while the test is carried out. Embryos can usually be thawed and transferred during the following cycle.