Preimplantation genetic diagnosis is the study of the chromosomal set of an embryo before its implantation during after conducting vitro fertilization. It is resorted to in order to ensure the absence of chromosomal abnormalities in a fetus.

Nowadays, two methods of genetic research are widely used, such as aCGH and FISH. The first one allows you to explore all 23 pairs of chromosomes, and the second one only part of the genome.

When is a study prescribed?

In the course of genetic counseling, a geneticist collects a history and anamnesis, compiles a pedigree, assigns karyotyping to future parents. Analyzing the collected information, the doctor decides on the need for pre-implantation diagnosis, determines the method that is suitable for a pair. Pre-implantation diagnosis can be prescribed if:

  • there is a history of at least one still pregnancy;
  • age of the biological mother is over 37;
  • parents have a child with a genetic abnormality or had a pregnancy with a chromosomal abnormality;
  • biological parents or their blood relatives have genetic diseases;
  • there is a history of more than two unsuccessful in vitro fertilization cycles.

ACGH method

Comparative genomic hybridization on aCGH microchips is currently the most comprehensive study of the number and structure of chromosomes. All pairs of the chromosome set are examined.

For analysis on the fifth day of development, all embryos grown in the laboratory are sampled, after which the zygotes are frozen. Freezing is performed because embryos of the fifth or sixth day of development are suitable for implantation, and the analysis is carried out for about three days. Further, special equipment is tested for DNA. According to the results of the analysis of the chromosome set, only those embryos are selected for which no anomalies have been detected.

The pre-implantation diagnosis of aCGH makes it possible to identify and discard embryos, implanting of which could lead to a spontaneous abortion, as well as to ensure that the unborn child will not suffer from genetic diseases.

FISH method

This research technique allows screening of no more than 12 pairs of chromosomes out of 23. However, it is quite informative if a number of gene abnormalities are suspected and may be quite sufficient.

For analysis using the FISH method, a cell biopsy is performed on the third day of embryo development. Next, geneticists carry out a qualitative and quantitative analysis of certain pairs of chromosome set.

This method also makes it possible to identify genome abnormalities at the preimplantation stage and prevent the implantation of genetically insignificant embryos.

FISH or aCGH?

The answer to this question depends on several aspects. Given that aCGH is much more informative, the price for this study is much higher, which does not always fit into the budget of future parents. According to statistics, the extraction of one of 8 cells on the third day of embryo development during FISH reduces the chance of survival by 22%. At the same time, there are cases when the aCGH test cannot be performed, because none of the embryos on the fifth day reached the required quality for the study.

Both methods have their strengths and weaknesses. It is possible to determine unequivocally which of them can only be used by a geneticist, relying on medical genetic indications and circumstances in each specific case.

We recommend reading:

  • Dear intended and soon becoming parents!Dear intended and soon becoming parents! Dear intended and soon becoming parents! Because of the spread of Internet rumors about the law adopted in the first reading in Ukraine prohibiting surrogacy motherhood, we consider it necessary to bring some clarity into the current situation. Who benefits from such rumors? First of ... more
  • Become a SurrogateBecome a Surrogate We sincerely thank you for your noble desire to become a surrogate mother. In the modern world, surrogate mothers are sometimes the only chance and the greatest gift for infertile couples and people who have decided to feel the joy of the birth of a new life. Only a special woman can become a surrog... more
  • IVF: embryo development after embryotransphereIVF: embryo development after embryotransphere Embryo implantation into uterine cavity is carried out under ultrasound control when patient lies on gynecological chair. A special silicone catheter is introduced into the cervical canal, through which the embryo (or several embryos) is transported to the uterus.The procedure takes 10-20 minutes, i... more
  • Female infertility. Types, causes, factors 2Female infertility. Types, causes, factors 2 Endocrine sterilityThis type of infertility occurs due to disruptions in the ovulation process caused by hormonal imbalances. For timely and regular ovulation responsible are:pituitary-hypothalamus-ovaries axis;thyroid;adrenal cortex.Disruptions in functioning at least at one of the listed levels en... more
  • Physical exercises improve the quality of spermPhysical exercises improve the quality of sperm Moderate regular (at least 30 minutes 3 times per week) physical activities help to improve the quality of sperm, as scientists claim.One in seven families in Britain has problems with conceiving a baby and thousands of such families apply for the procedure of IVF annually. In these circumstances ev... more

 



Entering your comment.



* All your information is strictly confidential and will not be disclosed

Please, contact our coordinator, who will give you the detailed plan of the programme you are interested in and provide further assistance.

Entering your number, please, add your country`s code.


* All your information is strictly confidential and will not be disclosed

Наверх
Закрыть
X

If you have any questions, please, leave you phone number or email. Our consultant will keep in touch with you to answer all your questions.



Special offer

Happy Easter!

We congratulate you on holidays and have prepared a promotion for you! To find out the details, leave your contact details and our coordinator will contact you as soon as possible!


For displaying of the personalized content this website uses cookies and other relevant technologies.By clicking OK or continuining using this website without changing cookies usage settings in your browser you give concent for the appliance of this technology.