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If a genetic disorder runs in my family, what are the chances that my children will have the condition?
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Inheritance

If a genetic disorder runs in my family, what are the chances that my children will have the condition?

Predicting the likelihood of passing on a genetic condition depends on the specific inheritance pattern and individual family history.

Inheritance Probabilities

The chance of passing on a genetic condition is calculated based on how the disorder is inherited:

  • Autosomal dominant: An affected person has a 50 percent chance of passing the altered gene to each child.
  • Autosomal recessive: Two carrier parents have a 25 percent chance with each pregnancy of having an affected child.
  • X-linked dominant: A man passes the condition to all his daughters but no sons. A woman has a 50 percent chance of passing it to any child.
  • X-linked recessive: A man passes the gene to all his daughters (who become carriers). A carrier woman has a 50 percent chance of having affected sons and a 50 percent chance of having carrier daughters.
  • Y-linked: Only males are affected; all sons of an affected man will inherit the condition.
  • Mitochondrial: Only females pass these variants to their children; all children of an affected woman may inherit the variant, while children of an affected man will not.

Important Considerations

It is vital to understand that these probabilities apply equally to each pregnancy. Having one child with a disorder does not change the risk for future children. Furthermore, factors such as reduced penetrance (where a person with a variant never develops symptoms) or variable expressivity can make risk prediction complex. Genetics professionals are the best resource for interpreting family history and genetic testing results to make informed health decisions.

Frequently Asked Questions

carrier mother has a 50 % chance of having a daughter who is a carrier (but usually not affected) and a 50 % chance of having a son who is affected.
No, the risk for each pregnancy is independent; having one affected child does not alter the probability for subsequent pregnancies.
n affected parent with an autosomal dominant disorder has a 50 % chance of passing the mutated gene to each child, so each pregnancy carries a 50 % risk of producing an affected child.
Reduced penetrance means that some individuals who carry the mutation may never show symptoms. In such cases, the statistical risk of having an affected child is lower than the theoretical 50 % (dominant) or 25 % (recessive) because some carriers will remain asymptomatic. Genetic counseling can help estimate the adjusted risk.
Yes, all children of a mother with a mitochondrial mutation inherit the mutation, so both sons and daughters can be affected. Sons of a father with a mitochondrial disorder are not affected because mitochondrial DNA is not passed from father to child.
Variable expressivity, reduced penetrance, de novo mutations, and polygenic contributions can all modify the actual risk beyond the basic 50 % or 25 % figures. Genetic counseling and testing can provide a more accurate assessment.
Cystic fibrosis is autosomal recessive. If both parents are carriers, each pregnancy has a 25 % chance of producing an affected child, a 50 % chance of a carrier child, and a 25 % chance of a child with two normal copies.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

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