Family planning for Leigh syndrome, like other mitochondrial diseases, can be complex because the condition may be inherited in different ways. Some assisted reproductive technologies (ART) and testing options are only available for certain inheritance patterns. This page is intended to help families better understand the available options and considerations.
In memory, Millie, USA
Assistive Reproductive Technologies
Available reproductive options for Leigh syndrome and other mitochondrial diseases differ depending on whether the condition is caused by nuclear DNA or mitochondrial DNA variants. Nuclear DNA variants are typically inherited similarly to many other genetic conditions and have several well-established reproductive testing options. In contrast, mitochondrial DNA inheritance is more complex and often requires consultation with a specialized mitochondrial disease or reproductive genetics center.
We also recognize that navigating these decisions can be emotionally difficult and overwhelming. Please explore the additional resources listed at the bottom of this page or contact us if you need additional support.
Prenatal Diagnosis (PND)
Prenatal diagnostic testing may be considered when a pregnancy is already underway. Chorionic villus sampling (CVS), typically performed between 11–13 weeks of pregnancy, analyzes placental cells, while amniocentesis, usually done between 15–17 weeks, analyzes fetal cells present in the amniotic fluid.
PND can detect known nuclear DNA variants in a pregnancy and is a well-established clinical option that may help inform pregnancy decisions and medical planning.
PND can also detect mitochondrial DNA variants. However, testing for mitochondrial DNA conditions is more complex because the relationship between the percentage of affected mitochondria (heteroplasmy) and disease severity is not fully understood for all variants. In addition, PND for mitochondrial DNA variants is only offered in limited specialized settings.
Preimplantation Genetic Testing (PGT)
Preimplantation genetic testing is an in-vitro fertilization (IVF) technique in which eggs and sperm are collected from prospective parents, the eggs are fertilized in the lab to create embryos, and then the embryos are screened for genetic variants prior to transfer to the uterus.
PGT is widely used for nuclear DNA variants associated with a variety of genetic conditions and is a well-established option routinely offered in clinical practice.
PGT for mitochondrial DNA variants has also shown promising results in research studies and may be available through some specialized mitochondrial disease clinics; however, it is still considered a research-based option focused on risk reduction rather than complete risk elimination.
Mitochondrial Replacement Therapy (MRT)
Women with affected mitochondria may be interested in an intervention called Mitochondrial Replacement Therapy (MRT), also called Mitochondrial Donation. MRT is a form of in-vitro fertilization in which a woman’s eggs are collected and their affected mitochondria is replaced with healthy mitochondria from a donor.
MRT is not currently available in the United States, although promising research and early clinical experience have been published in the United Kingdom. At this time, MRT is considered a risk reduction approach rather than a complete risk-elimination technique.
MRT is only relevant for women with mitochondrial DNA mutations.
Current Research on PGT and MRT for Mitochondrial DNA Inheritance
Quincy and Jack, USA
Recent research published in the New England Journal of Medicine (NEJM) reported encouraging early outcomes from studies performed in the United Kingdom using preimplantation genetic testing (PGT) and mitochondrial donation/replacement therapy (MRT/MD) for mitochondrial DNA disease.
- The papers reported 22 children born following PGT and 8 children born following mitochondrial donation in the United Kingdom.
- Most infants were born with undetectable or low levels of affected mitochondrial DNA.
- While these results are promising, experts emphasize that these approaches are currently considered risk-reduction rather than risk-elimination strategies.
- Additional research and long-term follow-up are still needed.
Papers:
For additional research papers related to reproductive options and mitochondrial disease, please visit “Genetics and Reproductive Strategies” section of our Papers page.
Other Family Planning Options
Available reproductive options for Leigh syndrome and other mitochondrial diseases differ depending on whether the condition is caused by nuclear DNA or mitochondrial DNA variants. Nuclear DNA variants are typically inherited similarly to many other genetic conditions and have several well-established reproductive testing options. In contrast, mitochondrial DNA inheritance is more complex and often requires consultation with a specialized mitochondrial disease or reproductive genetics center.
We also recognize that navigating these decisions can be emotionally difficult and overwhelming. Please reach out to us if you would like support or help finding resources.
Sperm Donation
Men with mitochondrial DNA variants cannot pass them on to their children. However, men with nuclear DNA variants can and may choose to use a sperm donor to avoid this.
Egg Donation
Women with either nuclear or mitochondrial DNA variants may choose to use an egg donor. Utilization of an egg donor allows affected women to carry their child but the nuclear DNA that contributes to the child will consist of the father and the egg donor.
Adoption
Adoption remains a family planning option for all individuals, whether affected with nuclear or mitochondrial DNA variants.
Support Resources
Media Library – Courageous Parents Network (not mito specific)
Listening, Reflecting, Healing (supportive genetic counseling)
Family Planning and Financial Considerations (by Global Genes)
