Genetic Testing-To Let You Know About Genes

Introduction

A medical test that is used to know about the changes in genes, chromosomes or proteins is known as genetic testing. It is done with the help of small samples of blood or body tissues. It is mainly preferred to determine the chance of a person of originating or passing on a genetic disorder. It has been developed enough so that the practitioners or professionals can often pinpoint those genes which are defective or missing. Numerous genetic tests are currently in use and more are getting developed.

Genetic Testing For Embryos

Genetic testing for embryos is widely used in fertility centres to uplift the chances of a healthy baby and live birth. Egg and sperm cells generally have 23 chromosomes. After fertilisation, a single-celled embryo is developed with 46 chromosomes. A cell having 46 chromosomes is known as euploid and an abnormal cell having more or fewer chromosomes is named as aneuploid. There are some drawbacks of aneuploid as it can result in congenital abnormalities like Down syndrome. There can be infertility, pregnancy loss, or IVF not resulting in pregnancy.

Embryonic cells continue to divide after fertilisation. After a matter of five to six days, 100 cells are there, each with 46 chromosomes if the cells are normal. One group of cells will result in becoming a baby and the other one as the placenta. A few cells that would later form the placenta at this stage can be cleared by an embryologist for testing known as preimplantation genetic testing for aneuploidy or PGT-A.

Genetic Testing During Pregnancy

Before giving birth to a child, a pregnant woman may decide to undergo chorionic villus sampling or amniocentesis. Even a blood test is also available for women to screen for some disorders. If there seems a possible problem in the screening test, doctors may recommend amniocentesis or chronic villus sampling. It is a test that happens between weeks 15 and 20 of a woman's pregnancy.

In order to perform genetic testing during pregnancy, the doctor will insert a hollow needle into the abdomen of the women to eject a tiny amount of amniotic fluid from around the developing fetus. The fluid can be tested to determine genetic problems as well as the sex of the child. If a risk seems to be there in premature birth, amniocentesis may be implemented to see how far the lungs of a baby have matured. But a person should be aware as amniocentesis contains a slight risk of inducing a miscarriage.

Genetic Testing Cost

Cost of genetic testing depends upon the nature and complexity of the test. The cost can be increased when more than a single test becomes crucial or if multiple family members must be tested to obtain a meaningful result. It may depend upon the country or a state where you are living.

Genetic Testing With IVF

Basically, there are two different types of genetic testing linked with IVF. They are named as preimplantation genetic screening (PGS) and preimplantation genetic diagnosis (PGD). The specialists of fertility conduct such tests to examine if the embryo has genetic abnormalities that often result in implantation and miscarriage, proving to be an unsuccessful IVF. Embryos found to have such blemishes are disqualified from being transferred to the mother's womb for pregnancy. Such types of testing can be helpful in increasing the likelihood of becoming pregnant and it is also helpful in improving live birth rates using IVF. Research has stated that genetic defects can be blamed as a major cause of live birth and failed pregnancy.

Preimplantation genetic screening is helpful in analysing embryo cells to determine if there is a normal amount of chromosomes known as euploidy. An unequal division of either egg cells or sperm can result in an embryo having very less or too many chromosomes. It can detect genetic conditions like Trisomy 21(Down syndrome) along with Trisomy 18 (Edward syndrome). On the other hand, preimplantation genetic diagnosis is there to analyze embryos that are created with IVF for a particular genetic disorder (s) one or both of the parents may carry. It can detect single gene defect disorders that can result in such diseases as sickle cell anaemia, muscular dystrophy, Tay-Sachs and cystic fibrosis.

Preimplantation genetic testing is helpful in lowering the risk of parents passing on a genetic disorder to their child. It also increases the possibility of healthy pregnancy along with successful birth to a child with the help of IVF with embryos free of genetic defects.