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Schizophrenia is a serious psychiatric disorder characterized by symptoms like hallucinations, delusions, and cognitive impairment (Schizophrenia Whitepaper). It affects roughly 1% of the population over a lifetime (Polygenic embryo screening and your family) and can be challenging for individuals and families to navigate, sometimes requiring long-term support from loved ones. Given its impact and tendency to run in families, many people wonder how much of schizophrenia is genetic versus influenced by other factors.

Genetic Factors in Schizophrenia

Research has shown that genetics play a substantial role in schizophrenia risk. Twin studies estimate that about 65%–80% of the variability in schizophrenia risk is due to heritable factors (The ultimate guide to schizophrenia). Note that heritability is a statistical concept that describes the extent to which genetic factors explain risk variations between people in a specific population, not the genetic risk for an individual to develop a certain disease (Genetics 101).

Family history is one clear indicator: having a parent or sibling with schizophrenia raises an individual’s lifetime risk to around 10%, compared to roughly 1% in the general population. If both parents are affected, the risk for a child can be as high as about 40–50% (The ultimate guide to schizophrenia). There is no single “schizophrenia gene”; instead, the illness is polygenic, meaning hundreds or thousands of genes each contribute a small effect to overall risk. Scientists have identified many genetic variants associated with schizophrenia, and even some rare mutations (such as certain copy number variants) that further increase risk (Schizophrenia Whitepaper).

Environmental Contributions

Despite the strong genetic influence, environmental factors also contribute to the development of schizophrenia (Polygenic embryo screening and your family). Research suggests that certain non-genetic factors – especially during early life – may elevate risk. Examples include complications or infections during pregnancy, exposure to viruses in utero (such as influenza), severe childhood trauma, or heavy cannabis use in adolescence (The ultimate guide to schizophrenia). However, these factors are not definitive causes; their links to schizophrenia are still being examined and should be viewed with caution (The ultimate guide to schizophrenia). In many cases, individuals with such exposures never develop schizophrenia, indicating that a complex interplay between genes and environment is at work.

Whole Genome Testing and Risk Prevention

Understanding the genetic predisposition to schizophrenia has opened the door to proactive risk mitigation. Orchid’s whole genome preimplantation genetic testing is a cutting-edge service that analyzes an embryo’s DNA for inherited risk factors before pregnancy. Through this comprehensive screening, Orchid provides a Genetic Risk Score for conditions like schizophrenia, enabling prospective parents undergoing IVF to identify which embryo has the lowest genetic risk (The ultimate guide to schizophrenia). Using embryo selection, families can significantly reduce the likelihood of schizophrenia in their future child. For example, one analysis showed that prioritizing the lowest-risk embryo could lower the relative risk of schizophrenia by roughly one-third.

While the risk cannot be eliminated, this knowledge empowers parents and doctors to make informed reproductive decisions and consider early interventions or monitoring if needed (Questions Answered about Screening Embryos for Genetic Predisposition to Chronic Diseases). Orchid’s testing gives families actionable insight into their future child’s mental health predisposition, helping them plan for a healthier future.

Not ready to screen embryos? Orchid’s couple’s preconception report helps you learn about your own genetic predisposition to common, chronic diseases and predicts the range of risks you can expect in future children based on the combination of your and your partner’s genetics. 

Conclusion

Schizophrenia arises from a complex interplay of genetic and environmental factors. A high hereditary component means that genes substantially influence risk, but are not causative on their own, as other factors such as  prenatal environment and lifestyle also play a role. For families concerned about schizophrenia, gaining clarity on inherited risk can be invaluable. Orchid’s whole genome testing services offer that clarity – providing sophisticated genetic insights that help families make informed, proactive choices about their reproductive options and risk-reduction strategies. If you’re concerned about inherited health risks, consider exploring Orchid’s genetic services and guides to empower your family’s future.