Pre-Implantation Genetic Testing for Monogenic or Single Gene Defects (PGT-M)
PGT-M or Pre-implantation genetic testing for monogenic/single gene defects is a test specifically designed to help reduce risk of having children who may have inherited conditions.
What is PGT-M?
The process of PGT-M or Pre-Implantation Genetic Testing for single gene or monogenic defects is carried out to rule out if the child has single gene disorders that may be inherited. The process is carried out if any one of the parents have a family history of genetic disorders or if one partner has been diagnosed with a genetic abnormality.
What are single gene disorders?
Single gene disorders are genetic condition that are caused by mutation of a single gene. They run in the family and in case a family has a history of single gene disorders, it is likely that it will be carried forward in their children.
Examples of some common Single Gene Disorders include
Cystic fibrosis (CF)
Sickle Cell Anemia
Duchene Muscular Dystrophy (DMD)
Fragile X Syndrome
Spinal Muscular Atrophy
How it works?
PGT-M is a testing procedure that is carried out when either one of the parents have a family history of single gene disorders or have been diagnosed with a genetic abnormality.
With the help of NGS (Next Generation Sequencing) embryos formed through the IVF process are tested and screened for any genetic abnormalities before they are processed for implantation in the uterus.
At MMC IVF, we have been early adapters of the NGS technology for genetic testing, which is superior and more accurate than real-time PCR techniques that being currently used.
NGS combines the power of single mutation detection and complete 24-chromosome aneuploidy testing. Both tests are performed simultaneously on the same embryo.
The test allows us to pick only the most viable embryos, most likely to succeed after this test, increasing the chances of implantation, a health pregnancy and joyous end result.
Genetic disorders that can be screened using PGT-M include:
Spinal Muscular Atrophy Type 1
Sickle Cell Disease
Fragile X Syndrome
Duchene Muscular Dystrophy
When is PGT-M recommended?
PGT-M is recommended when parents are likely to transmit a known genetic disorder to their children. Once PGT-M is performed, only healthy embryos free of genetic defects are transferred into the mother’s uterus. This procedure greatly reduces the risk of the child inheriting a genetic disorder and of late pregnancy termination.
PGT-M is performed for 3 major categories of genetic disorders:
Single Gene Defects
PGT-A or PGT-M?
Preimplantation Genetic Testing for Aneuploidies (PGT-A) is used to perform a general screening of embryos and does not look for a specific disease. PGT-M uses NGS technology to identify embryos at risk with specific genetic conditions.