Autosomal dominant means a genetic trait or condition can show up when a person inherits just one changed copy of a gene on a non-sex chromosome. If one parent has the condition-causing variant, each child usually has a 50% chance of inheriting it.

Quick Scoop

  • Autosomal = the gene is on one of the 22 non-sex chromosomes, so it can affect any sex.
  • Dominant = one altered copy is enough to cause the trait or disorder.
  • It often appears in successive generations of a family.
  • Examples include Huntington’s disease and some forms of Marfan syndrome.

Simple example

If a parent has an autosomal dominant condition, each child is independently at about a 1 in 2 chance of inheriting it. That does not mean exactly half of the children will always be affected; each pregnancy is its own separate chance.

One-line definition

An autosomal dominant condition is one that can be passed down from parent to child when a single mutated copy of a gene is enough to cause it.

If you want, I can also explain autosomal dominant vs autosomal recessive in a very simple table.