Genetic Tests (PGT)
PGT (pre-culturing genetic testing):
1. Diagnosis of sex therapy in fetuses before implantation
using FISH technique.
2. Evaluation of disorders of a number of chromosomes before
3. Investigation of chromosomal aneuploidy using 24Sure CGH
array technique, (sample sending).
4. Investigation of monogenetic mutations using NGS
technique (sending sample).
Pre-implantation Genetic Diagnosis
genetic diagnosis (PGD) is a technology in the science of reproduction that has
been considered to increase the likelihood of pregnancy and reduce fetal
genetic disorders. This technique is used to identify genetic defects and
prevent the transmission of certain diseases or genetic disorders to the fetus.
It is carried out by preventing the transmission of embryos with genetic
diseases to which couples are exposed, as well as for the selection of a
particular sex in certain diseases. Embryos examined for PGD are usually
present during the IVF process. In fact, using this technique, all genes
present on 23 pairs of fetal chromosomes are examined and defective genes that
carry inherited diseases are identified, thereby transmission and formation of
infected fetuses, as well as the birth of children with genetic disorders is
prevented. PGT includes two techniques:
PGD and PGS. Genetic screening in these two methods is to examine the
chromosomal abnormalities of the fetus.
Screening (PGS): A screening process that ensures
that a number of normal chromosomes are present and detects potential genetic
Genetic Diagnosis (PGD):
Cells from the embryo to test for specific genetic conditions before the embryo
is transferred to the uterus.
test is called a molecular karyotype and is especially used to identify the
cause of mental retardation or congenital anomalies, and is a high-resolution
technique for examining deletions or additions throughout the genome and
identifying chromosomal imbalances. Because this technique is able to detect
deletions and additions in the range of 5 to 10 kHz, it is called the Microarray
Comparative Genomic Hybridization (CGH array).
advantage of this method over the previous methods is that in the traditional
methods, many chromosomal deletions that are about 3 to 5 megabases in size are
not detected because these methods use a microscope and the ability to
distinguish deletions and add power. Microscope resolution is limited. As a
result, the changes are much smaller than the microscopic detection power,
which is not detected by invisible changes. In addition to high resolution, the
lack of time-consuming cell culture techniques speeds up the process.
Another advantage of this test over techniques
such as FISH and QF-PCR is the comprehensiveness of the CGH Array test. Chromosomal
deletions are also detected in the FISH technique. However, this technique is
used when clinical signs suggest the possibility of a chromosomal disorder, and
only one gene or a known part of the genome is examined. Nonetheless, the CGH
Array test, regardless of the clinical signs, makes it possible to examine a
large number of deletions and additions with just one test. The disadvantage of
the Array CGH method is that it does not detect balanced chromosomal
displacements. In this case, no part of the chromosome is removed or added. Rather,
only the displacement of parts of the chromosome is the cause of the disease,
so the CGH Array is not able to detect it.