Genetic testing of a couple should begin before trying to conceive, which is why it is called preconception testing.
An assessment of personal and family health history can highlight the risk of a hereditary disease that has already occurred in the family and may recur in the next generation. Another purpose of preconception genetic testing is to detect hidden predisposition to inherited diseases in the parents-to-be, which may not manifest itself until the offspring first develop a serious disease.
Preconception genetic testing usually includes
- Clinical genetic examination - analysis of personal and family history of both partners in the genetic consultation.
- Examination of chromosomes of both partners. Chromosomes are microscopically visible formations in the cell nucleus on which blocks of genes are located.
- In women, testing for predispositions for increased blood clotting (thrombophilic F5 gene mutations and prothrombin F2 gene mutations) and other congenital predispositions important for the response to assisted reproductive treatment and for the course of pregnancy (e.g. estimating the response to hormone treatment by testing the FSHR gene).
- Screening for hidden carrier gene changes (mutations) that may cause diseases with recessive inheritance in the offspring of carriers. In our population, these are mainly cystic fibrosis (CF) and spinal muscular atrophy (SMA). The newly introduced CarrierTest screens for mutations in a panel of 79 genes that may also cause other recessive diseases affecting, for example, the offspring's senses (e.g. hearing loss) or metabolism (inborn errors of metabolism).
- In men with a severe spermiogram disorder, examination of the loss (microdeletion) of material on the Y chromosome (azoospermic factor - AZF). According to the results of the preconception examination, it is possible to suggest the optimal course of treatment with assisted reproduction methods, to decide on the suitability of preimplantation examination (PGD or PGS) and to plan the care of future pregnancies (prenatal diagnosis)
Investigation of hereditary traits that can affect the fertility of parents and the health of offspring.
On average, one in five healthy people is a hidden carrier of a mutation in at least one of their genes. If both healthy partners are carriers of a mutation in the same gene, they can both pass the mutation on to their offspring at the same time. A mutation acquired from both parents will result in a severe autosomal recessive (AR) disease. Only females carry some of the mutations with this type of inheritance (the genes are located on the X chromosome) and the disease will only fully manifest in their sons if they pass the mutation on to them.
What genes and mutations does CarrierTest investigate?
CarrierTest investigates the hidden carrier status of 861 common - "key"- mutations in 79 recessive genes that cause more than 60 genetic diseases and conditions that can affect the offspring of healthy carriers. These include cystic fibrosis, spinal muscular atrophy, inborn errors of metabolism (e.g. phenyketonuria), visual and hearing impairment, musculoskeletal and skin diseases. Mutations in another group of genes may be relevant to the treatment of fertility disorders (thrombophilic profile, innate response to hormonal treatment of infertility) or may be lifestyle related (haemochromatosis, alpha1 antitrypsin deficiency).
What can the CarrierTest results be?
CarrierTest will completely rule out or confirm the presence of the key mutation. However, it does not exclude the carriage of all mutations in the genes under investigation, resulting in a residual "Residual Carrier Risk". From this risk is derived the risk of the offspring being affected (a measure of the genetic compatibility of the couple). For some genes, CarrierTest targets only certain mutations (for example, when testing for a thrombophilic profile). In these cases, the result is categorical (mutation proven/not proven).
The CarrierTest report is divided into four sections
- Carriage of mutations in genes associated with serious diseases in offspring.
- Carriage of gene mutations associated with environmentally influenced diseases.
- Mutations in a panel of genes that increase the disposition to clot blood (thrombophilic profile).
- Response to hormonal treatment of infertility (polymorphism of the FSH receptor gene).
The results of testing for recessive mutations and risk to offspring can be classified into three ca
No mutation has been found in either partner: the risk of their offspring being affected (residual risk) by the tested diseases is very significantly reduced.
Only one of the partners has been shown to carry a mutation in a particular gene: the residual risk of the offspring being affected by the tested diseases is low.
Both partners carry a mutation in the same gene: the risk of the offspring being affected is significantly increased (25% = 1/4).
Precautions when mutation carriage is detected
Precautions when mutations in the same gene are found in both partners at high risk of affecting the offspring:
Embryos created from the eggs and sperm of partners in an assisted reproduction programme (IVF) are screened and only embryos without an unfavourable combination of mutations are inserted into the mother's uterus.
Use of compatible sperm or eggs from donors
Prenatal examination of fetal cells
Prenatal examination of fetal cells after natural conception from chorionic villus sampling (CVS) or amniotic fluid collection (AMC).
Evidence of hereditary disease
Targeted detection of hereditary disease and available treatment as soon as possible after birth.
Identification of mutations in thrombophilic profile genes, mutations associated with therapeutic response and environmental diseases can help to target fertility disorders and modify the lifestyle of future parents.
Other treatment options
IVF with your own eggs
Infertility afflicts a large number of couples. We know how to help.
IVF with donated eggs
We have specialized in treatment with donated eggs since the clinic was founded. Thanks to our extensive database of donors, we can choose the most suitable one for you.
IVF with donated embryos
Thanks to our sophisticated egg donation program, we have the unique opportunity to offer infertile couples treatment with donated embryos.
The first step to parenting from the comfort of home
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