General Information on Genetic Screening
At MyEggBank (MEB), our goal is the same as yours: for you to have a healthy baby to take home at the end of this process. Genetic screening of egg donors is one way to get you closer to that goal. It is important to remember, however, that regardless of the means of conception, there is at least a 3-5% background risk for all newborns to have a birth defect.
In addition to screening egg donors, screening for the sperm source as well as screening in any resulting embryos and pregnancy will further help to reduce the risk for certain genetic conditions. You can discuss the option of preimplantation genetic testing for aneuploidy (PGT-A) with your fertility care provider, and more information about this embryo testing option is available below. You are encouraged to discuss prenatal testing options with your obstetrician.
Please be aware, there is no test available that can guarantee a healthy and developmentally typical child. All testing available is intended to reduce the risk for certain conditions in your future pregnancy and child but cannot eliminate it.
Genetic screening of potential egg donors is a two-part process: 1) genetic risk assessment based on the donor’s reported family history and 2) specific genetic tests to determine if a donor might be a carrier of certain genetic conditions. Each will be described below.
MyEggBank highly encourages you to speak with a certified genetic counselor to discuss your egg donor’s genetic testing results alongside your sperm source’s genetic testing results for your match. The genetic counselor may also go over your sperm source’s family history with you. You can request genetic counseling through your IVF center, or if they do not have one available, MEB can refer you to a certified genetic counselor to discuss your match. Any fees through the third-party genetic counseling service are separate from MyEggBank and would be paid directly to them.
Genetic Risk Assessment by Review of Medical Family History:
MyEggBank requires genetic risk assessment by a certified genetic counselor for all egg donors, during which a minimum of a three-generation family history is elicited and documented analyzed. All families are expected to have medical conditions amongst the various family members. The intention of family history review is to identify donor personal and family histories that may present an increased risk of serious medical conditions in offspring.
Personal and family histories of medical, developmental, and psychological conditions reported by the donor are detailed in the summary report, which is available for your review.
Donors may be declined if it is believed that their personal or family history significantly increases risk for certain serious medical issues in their offspring, above that of background risk.
Genetic risk assessment is only as accurate as the information provided at the time of evaluation. MEB cannot independently verify the accuracy of the donor’s reported family history, professional and educational history, or lifestyle.
Genetic Carrier Screening:
It is estimated that all human beings are carriers of multiple genetic conditions, often without a family history or awareness of their carrier status prior to genetic carrier screening.
The intention of genetic carrier screening in a reproductive setting is to identify increased risk for severe, childhood onset autosomal recessive and X-linked single gene disorders.
MyEggBank requires genetic carrier screening for egg donors in compliance with guidelines proposed by the American Congress of Obstetricians and Gynecologists (ACOG), the American College of Medical Genetics (ACMG) and the American Society of Reproductive Medicine (ASRM).
Generally, egg donors have been screened for genetic diseases that were recommended for testing by these organizations at the time the donor first donated with MEB. Because the recommended tests and the available genetic testing technologies continually evolve, egg donors within MEB may have completed different genetic tests. Your donor may not have had screening for diseases that can now be screened or for which the sperm source has been screened, as such testing may not have been performed or available at the time of donation. If the sperm source is found to be a carrier of a condition the donor has not been screened, the option of screening the donor for that specific condition can be explored.
Regardless of the test technology used or how recently testing has been performed, all genetic testing has limits in detection rate. Thus, a negative test result significantly reduces, but does not eliminate, the possibility that the donor could be a carrier of, or offspring could be affected with the tested condition. Residual risk after a negative test result is typically calculated and provided on the genetic carrier screening report or the carrier screening laboratory’s website. Refer to the carrier screening results for specific details.
No genetic carrier screening panel, regardless of the number of genes included on that panel, can screen for all genetic conditions. Therefore, an egg donor may be a carrier for a condition not included in genetic carrier screening performed at the time of her donation. Refer to the donor’s genetic carrier screening report for a list of genes included in testing at the time of donation.
Genetic Testing that MEB Will Not Request of a Donor:
It is not recommended by the above guidelines, nor will the donor be tested for:
- Autosomal dominant conditions (i.e., inherited cancer predisposing genes such as BRCA, Huntington disease, neurofibromatosis, etc.)
- Mild, treatable conditions with variable presentation (i.e., hereditary hemochromatosis type 1, Factor V Leiden)
- Direct to consumer testing (i.e., 23andMe or ancestry testing)
Optional Preimplantation Genetic Testing for Aneuploidy (PGT-A):
Many patients now elect to test their embryos for aneuploidy (chromosomal abnormalities). At MyEggBank we can offer a Single Euploid Guarantee for those who opt into that program via PGT-A testing.
PGT-A is used to screen embryos for certain types of chromosomal abnormalities, such as missing or extra chromosomes, that could cause implantation failure, miscarriage or aneuploidies associated with conditions such as Down syndrome. Through our PGT-A service, we will only report if the embryo has a euploid (chromosomally normal) result or aneuploid (chromosomally abnormal) result.
If PGT-A with MyEggBank’s Euploid Guarantee Program is selected, we will guarantee that you will have a minimum of one euploid embryo available for transfer or we will repeat the process at no charge to you with the donor of your choosing. Although PGT-A can be used to determine the sex of the embryos, MyEggBank’s Euploid Guarantee Program is not meant for sex selection. We cannot guarantee that your embryo(s) will have the sex of your choice.
Glossary of helpful terms:
Chromosomally abnormal; having too many or too few chromosomes. An example of aneuploidy is Down syndrome, which is often caused by having three copies of chromosome 21.
The type of genetic inheritance by which an affected person has inherited a gene variant from either the egg or sperm source. When one gamete source has a variant in an autosomal dominant gene, the chance of an affected offspring is 1 in 2 (50%). Males and females are equally likely to be affected with autosomal dominant conditions. An example of an autosomal dominant condition is neurofibromatosis.
The type of genetic inheritance by which an affected person has inherited a gene variant from both egg and sperm source. When both egg and sperm source carry a variant in an autosomal recessive gene, the chance of an affected offspring is 1 in 4 (25%). Males and females are equally likely to be carriers of or affected with autosomal recessive genetic conditions. An example of an autosomal recessive condition is cystic fibrosis.
The risk of a condition in the general population.
A carrier is someone who has one copy of their genes with a change in the DNA, or a variant, and the other copy has the typical DNA. The term carrier is used in reference to autosomal recessive and X-linked recessive conditions. Often, carriers are healthy and have no symptoms of the condition associated with that gene. However, there are some exceptions to that rule in which “manifesting carriers” may have some health effects associated with their carrier status, which would be noted on the carrier screening report.
Packages of genetic material in the cell. Each chromosome is made of a strand of DNA with hundreds of genes along the length of the chromosome. Human beings typically have a total of 46 chromosomes (arranged in 23 pairs) in our cells, half come from the egg and half from the sperm that led to our conception. The first 1 through 22 chromosome pairs are called autosomes and are numbered from largest to smallest and are the same for males and females. The 23rd chromosome pair is the sex determining pair. Females have two X chromosomes, and males have one X and one Y chromosome.
For more information on chromosomes visit: medlineplus.gov/genetics/understanding/basics/chromosome
The reproductive cell from the female ovary, containing half the genetic material needed to create and embryo and later baby.
Person contributing eggs for creating embryos.
What is created after a sperm fertilizes an egg and the resulting cells grow, divide and develop into what will become the fetus (baby) after 8 weeks. A preimplantation embryo is one that has not yet been implanted into the uterus, such as embryos in a laboratory environment.
Chromosomally normal; having the correct number of chromosomes.
An unborn human from 9 weeks after conception to the point of delivery of the pregnancy.
Eggs or sperm.
Individual units of hereditary information made up of a section of DNA on a chromosome. Genes come in pairs because they are located on chromosomes, which come in pairs. For more information on genes, visit: https://medlineplus.gov/genetics/understanding/basics/gene/
Individual(s) who will be carrying a pregnancy and/or legal parents of a fetus or child conceived using donor gametes.
Physical analysis of a set of chromosomes, often from a blood sample. A normal female karyotype is represented as 46,XX, whereas a normal male karyotype is represented as 46,XY.
Because no genetic carrier test has 100% detection rate, there is always a residual risk of being a carrier of a condition testing after a negative result. Residual risk calculations assume a negative family history of the condition testing and are based on the carrier frequency known in certain populations as well as the detection rate of the test. Residual risk estimates are included on the carrier screening result or on the carrier screening laboratory’s website. Often, residual risks are well below 1%.
The reproductive cell from the male, containing half the genetic material needed to create an embryo and later baby.
Person contributing sperm for creating embryos.
The type of genetic inheritance by which an individual has inherited a gene variant on the X chromosome. Females are often unaffected carriers, whereas males are affected. If a woman is a carrier of an X-linked recessive condition, male offspring have a 1 in 2 (50%) chance of being affected. Female offspring have a 1 in 2 (50%) chance of being a carrier. An example of an X-linked recessive condition is Duchenne muscular dystrophy.
A change in the DNA code of a gene that may affect the gene’s function and contribute to genetic disease. Pathogenic or likely pathogenic variants were previously referred to as mutations.
For more information about genetics, please visit: