autosomal dominant

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family pedigree

autosomal dominant

biology

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June 18, 2026

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family pedigree — family pedigree Pedigree of a family with a history of achondroplasia, an autosomal dominantly inherited disease. The solid symbols signify affected individuals.

Autosomal dominant inheritance describes a pattern of genetic disease transmission where a trait or condition can occur in either sex and be passed down by either parent. This occurs when an individual inherits a single copy of a mutated gene from one parent, along with a normal gene from the other. This condition is called heterozygosity.

Individuals with an autosomal dominant trait have a 50 percent chance of passing the mutated gene to each of their children. In some cases, inheriting two copies of the mutated gene (homozygosity) can lead to more severe effects or even be lethal. New mutations can also cause these disorders, meaning unaffected parents can have an affected child. Examples include achondroplasia and Huntington disease.1

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colour blindness
Inherited and acquired colour blindness
…blindness, by contrast, is an autosomal dominant disorder and therefore is not sex-linked and requires only one copy of the defective gene from either parent to be expressed. Achromatopsia is an autosomal recessive disorder, occurring only when two copies of the defective gene (one from each parent) have been inherited.…
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…blindness, by contrast, is an autosomal dominant disorder and therefore is not sex-linked and requires only one copy of the defective gene from either parent to be expressed. Achromatopsia is an autosomal recessive disorder, occurring only when two copies of the defective gene (one from each parent) have been inherited.…
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connective tissue disease
Hereditary disorders of connective tissue
…syndrome is inherited as an autosomal dominant trait; in other words, the gene involved is not a sex gene. No more than 15 percent of cases occur as an isolated instance in a family and may be attributable to a new mutation. Death is usually due to heart failure or…
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…syndrome is inherited as an autosomal dominant trait; in other words, the gene involved is not a sex gene. No more than 15 percent of cases occur as an isolated instance in a family and may be attributable to a new mutation. Death is usually due to heart failure or…
Read More

metabolic disease
Inheritance
Unlike autosomal recessive diseases, autosomal dominant diseases are expressed when only one mutant gene is present. These disorders show a strong family history, unless the condition arose from a new spontaneous mutation in an individual. A heterozygous individual has a 50 percent chance of passing the disorder to his…
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Unlike autosomal recessive diseases, autosomal dominant diseases are expressed when only one mutant gene is present. These disorders show a strong family history, unless the condition arose from a new spontaneous mutation in an individual. A heterozygous individual has a 50 percent chance of passing the disorder to his…
Read More